Regional & statewide opportunities & solutions

              Oklahoma Comprehensive Water Plan
Supplement to Executive Report
Regional & Statewide
Opportunities & Solutions
OCWP Regional and Statewide Opportunities and Solutions
The following report was developed by the Oklahoma Water Resources Board and CDM, the OCWP’s lead engineering firm, to present the results of OCWP analyses with particular emphasis on planning basins (i.e., "hot spots") with the most significant anticipated water supply challenges and potential options based upon physical supply availability, permit availability, and water quality constraints..
The Oklahoma Water Resources Board respectfully requests public review of this document. Comments should be provided at any of the thirteen OCWP Feedback and Implementation meetings or in writing to the OWRB by May 31, 2011. Information from this report will be published in the Executive Report of the 2012 Update of the Oklahoma Comprehensive Water Plan.
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Contents
Section 4 – Regional and Statewide Opportunities and Solutions
4.1 Statewide Water Supply “Hot Spots” and Effective Alternatives .......... 4-1
4.1.1 Hot Spot Identification Methodology ....................................... 4-1
4.1.1.1 Surface Water ........................................................ 4-1
4.1.1.2 Groundwater .......................................................... 4-2
4.1.2 Results of Hot Spot Identification ............................................ 4-4
4.1.3 Effective Supply Options for the Hot Spot Basins ................... 4-7
4.1.3.1 Summary of Solutions for Basin 22 (Walnut Bayou) .................................................................... 4-7
4.1.3.2 Summary of Solutions for Basin 26 (Beaver Creek-3) ................................................................. 4-9
4.1.3.3 Summary of Solutions for Basin 34 (Lower North Fork Red River 3) ...................................... 4-12
4.1.3.4 Summary of Solutions for Basin 36 (Upper North Fork Red River-1) ...................................... 4-14
4.1.3.5 Summary of Solutions for Basin 38 (Salt Fork Red River-1) ......................................................... 4-17
4.1.3.6 Summary of Solutions for Basin 40 (Prairie Dog Town Fork Red River-1) and Basin 41 (Prairie Dog Town Fork Red River-2) .................. 4-20
4.1.3.7 Summary of Solutions for Basin 42 (Elm Fork of the Red River-3) .............................................. 4-24
4.1.3.8 Summary of Solutions for Basin 51 (Middle North Canadian River) ......................................... 4-27
4.1.3.9 Summary of Solutions for Basin 54 (Upper North Canadian River-3) ..................................... 4-30
4.1.3.10 Summary of Solutions for Basin 55 (North Canadian Headwaters) and Basin 66 (Cimarron Headwaters) ....................................... 4-33
4.2 Aquifer Recharge .................................................................................... 4-36
4.2.1 Site Screening Process ........................................................... 4-36
4.2.2 Recommended Sites for Recharge Pilot Project ................... 4-38
4.3 Marginal Quality Water .......................................................................... 4-40
4.4 Drinking Water Infrastructure Needs Assessment by Region ............. 4-48
Section 4
Contents
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Figures
4-1 Hot Spot Basins
4-2 Location of Sites that Passed Fatal Flaw and Threshold Screening
4-3 Approach for Assessing Uses of MQW
4-4 Statewide Drinking Water Infrastructure Cost Summary by Region
Tables
4-1 Top Twelve Basins with Most Significant Water Supply Challenges (ordered by basin number)
4-2 Drivers for the Top Twelve Basins with Most Significant Water Supply Challenges
4-3 Summary of Water Supply Options for Basin 22
4-4 Summary of Water Supply Options for Basin 26
4-5 Summary of Water Supply Options for Basin 34
4-6 Summary of Water Supply Options for Basin 36
4-7 Summary of Water Supply Options for Basin 38
4-8 Summary of Water Supply Options for Basins 40 and 41
4-9 Summary of Water Supply Options for Basin 42
4-10 Summary of Water Supply Options for Basin 51
4-11 Summary of Water Supply Options for Basin 54
4-12 Summary of Water Supply Options for Basins 55 and 56
4-13 Potential Uses of MQW to Meet Water Demand
4-14 Statewide Drinking Water Infrastructure Cost Summary by Category
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Section 4
Regional and Statewide Opportunities and Solutions
4.1 Statewide Water Supply "Hot Spots" and Effective Alternatives
This section documents the methods and results of the Oklahoma Comprehensive Water Plan (OCWP) analyses to determine the basins in Oklahoma with the most significant statewide water supply challenges, referred to herein as "hot spots." Water supply issues were determined based on physical supply availability, permit availability, and water quality constraints. A detailed assessment of the most effective supply options for the hot spot basins was conducted and is detailed as part of this report.
4.1.1 Hot Spot Identification Methodology
Hot spots were identified based on the physical supply availability, permit availability, and water quality metrics for each of the 82 OCWP basins. These analyses were based on data presented in the OCWP Watershed Planning Region Reports and Basin Reports. The criteria used to identify hot spots were developed based on quantitative metrics to provide an objective methodology. For the initial identification, hot spots were evaluated independently for Oklahoma's three major categories of supply – surface water, alluvial groundwater, and bedrock groundwater. The methodology used to identify the hot spots for each supply category is presented below.
4.1.1.1 Surface Water
Surface water supplies from reservoirs and direct river diversions are major supply sources for many of the 82 OCWP basins. Physical supply availability, permit availability, and water quality criteria were used to account for current water uses and the projected change in demand from 2010 to 2060. Details on each of the criteria are presented below.
Physical Supply Availability Criteria
The surface water supply availability for each basin was calculated based on the historic streamflow, unused storage in existing reservoirs, and future demand. The water supply availability results, shown in the Basin Reports, quantify how large a surface water gap will be (magnitude) and how often a gap is expected to occur (probability). The hot spot analyses were based on 2060 demand, representing the most significant issues anticipated in the 50-year OCWP planning horizon.
The most significant physical supply issues are gaps that occur frequently and are large in magnitude. Thus, physical water supply criteria were developed to incorporate both the magnitude and probability of gaps for each basin. The magnitude of a gap is represented by the likely size of a gap (median gap of all months with gaps) based on monthly analyses of the 58-year streamflow period of record (Water Years 1950 to 2007). The evaluation Section 4
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also assesses the severity of the gap in the basin by dividing the size of the gap by the total demand in the basin. This approach provides a common basis of analysis for large and small basins alike. The probability of a gap occurring in at least one month of the year, expressed as a percent, was used to indicate the likelihood of gaps.
The result is an index that was calculated for each of the 82 basins in the state. The 82 basins were ranked based on their physical supply availability index.
Permitting Criteria
The availability of new permits is based on Oklahoma Water Resources Board (OWRB) analyses of annual streamflow data. Therefore, permit availability is generally correlated with the physical availability results, but some differences do occur. An analysis of permit availability for each basin was conducted in 2010 (Water Supply Permit Availability Report, October 2010). The results of those analyses were used to rank the 82 basins. Basins that are already over-appropriated were considered to have the most severe permitting constraints.
Water Quality Criteria
The impact of water quality on the use of a supply source is driven by numerous factors, including the specific constituents of concern to a given demand sector and the economic viability of treating the water to meet the end users' water quality requirements. For the purpose of this analysis, OWRB staff developed a surface water quality condition index for streams and reservoirs to be used for assessing the relative level of water quality issues prevalent in each basin. This analysis was conducted to assist in the delineation of basins as potential "hot spots," but should not be considered an absolute characterization of specific water bodies.
The method for determining a water quality condition score was similar for streams and lakes. For both water body types, both a trend and standards index score were calculated using water quality data (primarily from the OWRB Beneficial Use Monitoring Program) and recent trending analyses by OWRB staff.
The trend and standard index scores were combined to determine a water quality condition score. The trend and standard index scores are weighted equally (50 percent/ 50 percent) to get a composite score that is ranked to determine the relative water quality condition score.
4.1.1.2 Groundwater
Groundwater in Oklahoma plays a key role in meeting water demand in basins where surface water is not readily accessible or groundwater supplies are more economical to develop. Groundwater supplies were evaluated separately for alluvial aquifers and bedrock aquifers. The groundwater criteria focus on physical supply availability metrics.
The water quality of Oklahoma's aquifers can be highly variable. Unlike surface water, there is no statewide water quality data collection program or database of water quality for groundwater. Additionally, groundwater quality can vary greatly from well to well within the Section 4
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same aquifer. The Water Quality in Oklahoma Report lists aquifers with known water quality issues. There are known constraints for public water providers (e.g., Blaine aquifer and Arbuckle-Timbered Hills); however, these aquifers are still used for agricultural or industrial uses. Although groundwater quality can be a significant factor in water supply analyses, the lack of a robust groundwater quality database precluded the use of groundwater quality as a criterion for this statewide evaluation.
Permit availability for groundwater sources has been evaluated (Water Supply Permit Availability Report, October 2010), but those analyses concluded that the use of groundwater to meet in-basin demand is not expected to be limited by the availability of permits for any of the 82 basins through 2060. Therefore, basins cannot be distinguished on the basis of permit availability, and no permit availability criteria were included in this analysis.
In the OCWP Basin Reports, groundwater supplies were evaluated separately for bedrock aquifers and alluvial aquifers, based on differences in how recharge was represented. Alluvial aquifer recharge was based the basin's streamflow (58-year period of record), while bedrock aquifer recharge was based on average annual recharge estimates. Storage depletions occur when demand exceeds recharge (supply). Storage depletions indicate the sustainability of aquifer use in a basin and the potential for localized decreases in available groundwater supplies. Separate criteria were developed for alluvial and bedrock groundwater as described below.
Alluvial Groundwater
Physical alluvial groundwater availability was determined using two components representing the severity of groundwater depletions and the rate of depletions relative to the amount of water in storage in each basin. As with surface water gaps, frequently-occurring large alluvial groundwater depletions are more concerning than infrequent or smaller depletions. Alluvial groundwater supplies are subject to hydrologic cycles of wet and drought periods, and thus, the occurrence and size of depletions will vary from year to year.
Two components were analyzed to assess alluvial groundwater supply availability. The first component is the severity of alluvial groundwater depletions relative to the amount of water in storage (to assess the rate of depletion relative to available supplies) occurring in 2060. The alluvial groundwater scores were ranked for the 82 basins.
The second component of the physical alluvial groundwater availability score was derived from using only the size and probability of alluvial groundwater depletions; storage was not considered. The 82 basins were ranked based on severity of depletions of the alluvial groundwater aquifer. This component symbolizes the magnitude of the alluvial storage depletion in the basin.
These two components were combined to develop an alluvial groundwater physical availability ranking for each basin. Section 4
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Bedrock Groundwater
The physical availability of bedrock groundwater was scored using a method similar to that used for alluvial groundwater. However, since bedrock groundwater supplies are recharged at more constant rates (much less hydrology-dependent from year to year), the probability of bedrock storage depletions is not applicable – in a given future year, bedrock groundwater depletions either will or will not occur, based on whether the demand exceeds the relatively-constant rate of recharge in that year.
The two components of the physical availability score for bedrock groundwater are shown below. The first component relates the median annual depletion to the amount of bedrock groundwater storage in a basin, excluding minor aquifers, again representing the severity of the rate of depletion relative to available supplies. The bedrock groundwater scores were ranked for the 82 basins.
The second component ranks each basin's median annual depletion of bedrock groundwater supplies to other basins' bedrock groundwater depletions.
These two components were used to develop a physical bedrock groundwater availability ranking for each basin.
4.1.2 Results of Hot Spot Identification
An overall hot spot ranking was developed for surface water and groundwater availability of each basin. For surface water, the physical supply availability, permit availability, and water quality results were combined to determine an overall score and ranking for the basins. As discussed above, alluvial and bedrock groundwater hot spot rankings were based solely on physical supply availability analyses.
In order to determine the basins' overall scores and rankings, a weighting of each of the criteria was needed. The following weights were assigned for surface water.
 Physical Supply Availability = 50 percent
 Water Quality = 20 percent
 Permit Availability = 30 percent
The heavier weighting on physical supply availability reflects the critical nature of having a physical supply shortage. Permit availability, while critical for utilizing a surface water supply, was weighted slightly lower because permit availability is dependent on surface water availability. Water quality is also highly important in meeting various water users' needs, but was viewed as less critical as the physical and permitting criteria because treatment technologies can be applied in many situations to resolve differences between raw water quality and the users' water quality requirements.
The same approach was taken to develop a composite score for alluvial and bedrock groundwater for each of the 82 basins, but solely based on physical supply availability as discussed above. Section 4
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These three lists (ranking of basins for surface water hot spots, alluvial groundwater hot spots, and bedrock groundwater hot spots) were reviewed with OWRB staff to validate the results against historical insights and known areas of concern. Upon that validation, a total of 12 basins were selected by OWRB for subsequent analysis regarding the cause of the supply issues and more detailed investigations regarding potential water supply solutions for those basins. The 12 basins include the top 7 ranked surface water supply hot spot basins, the top 4 ranked alluvial groundwater supply hot spot basins, and the top 6 ranked bedrock groundwater supply hot spots, listed in Table 4-1 and shown on a map in Figure 4-1. Because some basins are among the top hot spots in more than one supply category, the combined total number of basins is 12.
Table 4-1. Top Twelve Basins with Most Significant Water Supply Challenges (ordered by basin number) Basin Basin Name
22
Walnut Bayou
26
Beaver Creek - 3
34
Lower North Fork Red River - 3
36
Upper North Fork Red River - 1
38
Salt Fork Red River - 1
40
Prairie Dog Town Fork Red River - 1
41
Prairie Dog Town Fork Red River - 2
42
Elm Fork Red River - 1
51
Middle North Canadian River
54
Upper North Canadian River - 3
55
North Canadian Headwaters
66
Cimarron Headwaters
Figure 4-1 – Hot Spot Basins Section 4
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A brief summary of the key drivers for the 12 basins' designation as a hot spot basin is provided in Table 4-2.
Table 4-2. Drivers for the Top Twelve Basins with Most Significant Water Supply Challenges Basin Basin Name Major Drivers
22
Walnut Bayou
Hot Spot for surface water and bedrock groundwater. The surface water hot spot is driven by physical availability (ranked #1). Bedrock groundwater storage depletions are ranked #10 for both overall size and portion of major aquifer storage depleted.
26
Beaver Creek - 3
Surface water hot spot. The surface water hot spot is driven by physical availability (ranked #5) and potential water quality issues (ranked #9).
34
Lower North Fork Red River - 3
Hot spot for surface water. The surface water hot spot is driven by all three criteria: physical availability (ranked #6), permit availability (ranked #11) and potential water quality issues (ranked #5).
36
Upper North Fork Red River - 1
Alluvial groundwater hot spot. The basin is the worst alluvial groundwater hot spot, where alluvial groundwater storage depletions are ranked #2 for overall size and ranked #1 for the portion of major aquifer storage depleted.
38
Salt Fork Red River – 1
Hotspot for alluvial groundwater and bedrock groundwater. Both the alluvial groundwater and bedrock groundwater storage depletions are ranked highly (bad) for the portion of major aquifer storage depleted, ranked #3 and #5, respectively. The basin is also highly ranked (bad) for the size of alluvial groundwater and bedrock groundwater storage depletions, ranked #13 and #8, respectively.
40
Prairie Dog Town Fork Red River – 1
Hot spot for surface water and bedrock groundwater. The surface water hot spot is driven by moderately high rankings (bad) in all three criteria: physical availability (ranked #17), permit availability (ranked #18) and potential water quality issues (ranked #16). Bedrock groundwater hot spot storage depletions have high rankings (bad) for both criteria; ranked #6 for overall size and ranked #11 for the portion of major aquifer storage depleted.
41
Prairie Dog Town Fork Red River – 2
Bedrock groundwater hot spot. The basin is the second worst bedrock groundwater hot spot, where storage depletions are ranked #4 for overall size and ranked #7 for the portion of major aquifer storage depleted.
42
Elm Fork Red River – 1
Hot spot for surface water and alluvial groundwater. The surface water hot spot is driven by physical availability (ranked #7) and has a moderately high ranking (bad) for potential water quality issues (ranked #19). The basin is the second worst alluvial groundwater hot spot, where storage depletions are ranked #1 for overall size and ranked #3 for the portion of major aquifer storage depleted.
51
Middle North Canadian River
Hot spot for surface water and alluvial groundwater. The basin is the worst surface water hot spot and the third worst alluvial groundwater hot spot. The surface water hot spot is driven by physical availability (ranked #6) and permit availability (ranked #1). The basin is the third worse alluvial groundwater hot spot, where storage depletions are ranked #6 for overall size and ranked #2 for the portion of major aquifer storage depleted.
54
Upper North Canadian River - 3
Bedrock groundwater hot spot. The basin is the worst bedrock groundwater hot spot, where storage depletions are ranked #8 for overall size and ranked #2 for the portion of major aquifer storage depleted.
55
North Canadian Headwaters
Bedrock groundwater hot spot. The basin is the fifth worst bedrock groundwater hot spot, where storage depletions are ranked #12 for overall size and ranked #1 for the portion of major aquifer storage depleted.
66
Cimarron Headwaters
Hot spot for surface water and bedrock groundwater. The surface water hot spot is driven by physical availability (ranked #12), permit availability (ranked #9). The basin is the third worst bedrock groundwater hot spot, where storage depletions are ranked #7 for overall size and ranked #4 for the portion of major aquifer storage depleted. Section 4
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4.1.3 Effective Supply Options for the Hot Spot Basins
4.1.3.1 Summary of Solutions for Basin 22 (Walnut Bayou)
Basin 22 (Walnut Bayou) is a surface water and bedrock groundwater hot spot. Surface water issues are mainly due to the basin's low physical availability of streamflow, though the basin also has relatively little available streamflow for new permits, and has fair water quality. The storage depletions are expected to provide water supply challenges based on the overall size of the depletions and for the rate of storage depletions relative to the amount of storage in the Antlers bedrock aquifer. More detailed information on this basin is available in the OCWP Water Supply Hot Spot Identification and Analysis report and the Lower Washita Region Planning Report. In addition to surface water gaps and bedrock groundwater storage depletions, alluvial groundwater storage depletions may occur by 2050. Six categories of supply options for mitigating the projected surface water gaps and groundwater storage depletions in Basin 22 are summarized in Table 4-3 and described in the text below.
Table 4-3. Summary of Water Supply Options for Basin 22 Water Supply Option Option Feasibility
Demand Reduction
 Moderately expanded Municipal and Industrial conservation measures and increased sprinkler irrigation efficiency
 Significantly expanded Municipal and Industrial conservation measures and shift to crops with lower water demand
 Short- to long-term solution that may reduce up to 70% of surface water gaps and alluvial groundwater storage depletions, and up to 45% of bedrock groundwater storage depletions
Increased Reliance on Surface Water
 Increased use of surface water supplies, without reservoir storage
 Not feasible
Increased Reliance on Groundwater
 Increased reliance on the Antlers bedrock aquifer instead of increased surface water and alluvial groundwater use
 Short-term solution; not sustainable and may not be cost-effective in the long term
Marginal Quality Water Use
 Use of marginal water quality sources
 No significant sources identified; site-specific potential for reuse of oil and gas flowback and produced water for oil and gas drilling and operations
Reservoir Storage
 Development of new reservoirs
 Not feasible
Out-of-Basin Supplies
 Potential Caddo Creek, Courtney, Durwood, and Ravia reservoirs
 Supply from Lake Texoma
 Potential long-term solution
Demand Reduction
Demand reduction could reduce surface water gaps or groundwater storage depletions through expanded permanent conservation measures. Increasing the irrigation efficiency in the Crop Irrigation demand and implementing moderately expanded conservation measures for Municipal and Industrial demands (Scenario I conservation, as defined in the OCWP Water Demand Forecast Report) could reduce the demand by 820 acre-feet per year (AFY) and reduce the size of the annual surface water gaps in 2060 by about 44 percent, to a value of 460 AFY, alluvial groundwater storage depletions in 2060 by about 25 percent, to a value of 90 AFY, and bedrock groundwater depletions in 2060 by Section 4
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about 18 percent, to a value of 770. This conservation measure could benefit users throughout the basin and should be considered as a short- to long-term water supply option.
Current crops are predominantly wheat and corn for grain and, to a lesser extent, forage crops. A shift from crops with high water demand (e.g., corn for grain and forage crops) to low water demand crops such as sorghum for grain or wheat for grain and substantially expanded municipal and industrial (M&I) conservation measures (Scenario II conservation, as defined in the OCWP Water Demand Forecast Report) could reduce demand by an additional 710 AFY. These additional conservation measures could reduce the size of the annual surface water gaps in 2060 by an additional 28 percent, to a value of 230 AFY, alluvial groundwater storage depletions in 2060 by an additional 42 percent, to a value of 40 AFY, and bedrock groundwater depletions in 2060 by an additional 27 percent, to a value of 520 AFY. These measures could benefit users throughout the basin and should be considered as a long-term water supply option.
Increased Reliance on Surface Water Supplies
Use of surface water to meet local demand in Basin 22 through 2060 is not expected to be limited by the availability of permits. However, there is a very high probability of surface water gaps starting in 2020 for the baseline demand projections. Increased reliance on surface water use would increase the size and probability of these gaps. Therefore, increased reliance on Basin 22 surface water supplies is not recommended.
Increased Reliance on Groundwater Supplies
Bedrock groundwater supplies, mainly from the Antlers bedrock aquifer, are used to meet 75 percent of the demand in Basin 22. The Antlers aquifer underlies most of the southern half of the basin and has substantial stored groundwater in the basin. The projected growth in surface water and alluvial groundwater use could instead be supplied by the Antlers bedrock aquifer, but would result in small (1,270 AFY) increases in projected bedrock groundwater storage depletions. The development of additional bedrock groundwater supplies should be considered a short-term water supply option. Over the long term, the increased depletions of stored water may lead to decreased well yields and increased pumping costs, making demand reduction and other supply options more sustainable and cost-effective.
The majority of current alluvial groundwater rights are in non-delineated minor aquifers; therefore, the typical yields, volume of stored water, and water quality are unknown. Increased reliance on these supplies is not recommended without site-specific information.
Reservoir Storage
The development of reservoir storage in Basin 22 is not recommended. The OCWP Reservoir Viability Study evaluated the potential for reservoirs throughout the state; no viable sites were identified in Basin 22. Additionally, basin-level evaluations in the Lower Washita Watershed Planning Region Report indicate that there is insufficient streamflow to provide sufficient water supply yields to meet the growth in the demand in the basin. Section 4
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Out-of-Basin Supplies
Out-of-basin supplies would be among the most costly of options, but could eliminate the potential for surface water gaps and groundwater depletions. The development of out-of-basin supplies should be considered as a long-term water supply option for users throughout the basin. However, due to the scale and complexity of developing out-of-basin supplies, the cost-effectiveness of these supplies should be evaluated against other options on a local level. Potential out-of-basin supplies include four potential reservoirs and Lake Texoma. Caddo Creek Reservoir, Courtney Reservoir, Durwood Reservoir, and Ravia Reservoir were identified in the OCWP Reservoir Viability Study report as nearby viable reservoir sites. Caddo Creek and Courtney Reservoir sites are approximately 15 miles from the center of Basin 22. Durwood and Ravia reservoir sites are approximately 30 miles from the center of Basin 22. Lake Texoma is approximately 40 miles from the center of Basin 22, and would likely require advanced treatment for M&I use due to total dissolved solids (TDS) concentrations. With new terminal storage of about 900 acre-feet (AF), a 14-inch diameter pipe would be needed to bring out-of-basin supplies at a constant flow rate into Basin 22 for further distribution to users. With no terminal storage and variable flows in the pipeline, a 24-inch diameter pipeline would be needed. Unlike many hot spot basins, Basin 26 is not served by any alternatives in the statewide water conveyance system (OWRB Water Conveyance Alternatives report).
Marginal Water Quality Water Use
The OCWP Marginal Quality Water Work Group Final Report identified areas where there is potential for use of marginal quality water (MQW) to offset a significant amount of future demand. However, Basin 22 was not found to have significant marginal quality sources or significant potential to offset demand with MQW. The Oil and Gas demand sector could potentially use MQW from oil and gas flowback or produced water for drilling and operational activities. Opportunities to reuse flowback or produced water should be considered on an individual well field basis for cost-effectiveness relative to other available supplies.
Summary of Supply Options
Short-term water supply options for Basin 22 include reducing M&I demands through moderately expanded conservation measures and increasing sprinkler irrigation efficiency, and increased use of the Antlers aquifer. Long-term water supply options may include out-of-basin supplies from four potential reservoirs or Lake Texoma. However, due to the scale and complexity of these long-term supplies, the cost-effectiveness of these supplies should be evaluated against other options on a local level.
4.1.3.2 Summary of Solutions for Basin 26 (Beaver Creek-3)
Basin 26 (Beaver Creek-3) is a surface water hot spot, where surface water issues are mainly associated with the basin's low physical availability of streamflow, lack of available streamflow for new permits, and poor water quality. More detailed information on this basin is available in the OCWP Water Supply Hot Spot Identification and Analysis report and the Beaver-Cache Watershed Region Planning Report. Six categories of supply Section 4
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options for mitigating the projected surface water gaps and groundwater storage depletions in Basin 26 are summarized in Table 4-4 and described in the text below.
Table 4-4. Summary of Water Supply Options for Basin 26 Water Supply Option Option Feasibility
Demand Reduction
 Moderately expanded conservation for Municipal and Industrial sector and increased Crop Irrigation efficiency
 Substantially expanded Municipal and Industrial conservation
 Short- to long-term solution that may eliminate surface water gaps and reduce 20% of groundwater depletions
Increased Reliance on Surface Water
 Increased use of surface water supplies, without reservoir storage
 Not feasible
Increased Reliance on Groundwater
 Increased reliance on the non-delineated minor groundwater sources currently used
 Short to long-term solution depending on local yield and cost-effectiveness
Marginal Quality Water Use
 Use of marginal water quality sources
 No significant sources identified
Reservoir Storage
 Development of new reservoirs
 Not feasible
Out-of-Basin Supplies
 Waurika Lake Master Conservancy District
 Cookietown Reservoir
 Potential long-term solutions
Demand Reduction
Demand reduction could reduce surface water gaps and groundwater storage depletions through expanded permanent conservation measures. Increasing the irrigation efficiency in the Crop Irrigation demand sector and moderately expanded conservation measures for the M&I demand sector (Scenario I conservation, as defined in the OCWP Water Demand Forecast Report) could together reduce the demand by 410 AFY and reduce the size of the annual surface water gaps by up to 90 percent in 2060, to a value of 10 AFY. These same conservation measures are only expected to reduce groundwater depletions in minor bedrock aquifers by about 20 percent in 2060, to a value of 250 AFY. Moderately expanded conservation measures could benefit users throughout the basin and should be considered as a short– to long-term water supply option. Surface water gaps could be eliminated with substantially expanded conservation measures (Scenario II conservation, as defined in the OCWP Water Demand Forecast Report) for the M&I demand sector, which includes implementation of a high efficiency plumbing code ordinance, increased education, and widespread adoption of conservation water rates.
Increased Reliance on Surface Water Supplies
There is a high probability of surface water gaps in supplies from Cow Creek starting in 2020 for the baseline demand projections. Increased reliance on surface water supplies, which have relatively poor water quality, would increase the size and probability of these gaps. Therefore, increased reliance on Basin 26 surface water supplies is not recommended.
Increased Reliance on Groundwater Supplies
There are no major aquifers in Basin 26. The majority of groundwater rights in Basin 26 are in non-delineated minor bedrock aquifers. Increased reliance on these supplies is not Section 4
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recommended on a basin-scale. Because of the low well yields associated with minor aquifers, these supplies are unlikely to meet the needs of large-scale users and the viability of these supplies is site-specific.
Reservoir Storage
The development of reservoir storage in Basin 26 does not appear to be feasible. The OCWP Reservoir Viability Study evaluated the potential for reservoirs throughout the state; no viable sites were identified in Basin 26. Basin-level evaluations in the Beaver-Cache Watershed Planning Region Report indicated that if a suitable site could be identified, a reservoir with 900 AF of storage at the basin outlet and new conveyance infrastructure could meet the basin's entire growth in demand from 2010 to 2060. However, a detailed evaluation of the feasibility of any reservoir would be needed and should include consideration of existing land ownership, costs, geology, water quality, and permitting/ compact obligations.
Out-of-Basin Supplies
Out-of-basin supplies from the Waurika Lake Master Conservancy District (Waurika MCD) are a major source of supply for Basin 26, where the cities of Duncan and Comanche received over 5,000 AFY of supply in 2007. Increased reliance on these out-of-basin supplies, with new infrastructure, could mitigate surface water gaps. However, existing users and allocation of the lake's supplies would need to be considered. If suitable supplies could be allocated from the Waurika MCD, an additional 180 AFY of out-of-basin supplies from Waurika Lake, which is approximately 10 miles away from the center of the basin, could meet the M&I demand. With new terminal storage of less than 100 AF, a 6-inch diameter pipe would be needed to bring out-of-basin supplies at a constant flow rate into Basin 26 for further distribution to users. With no terminal storage and variable flows in the pipeline, a 6-inch diameter pipeline would also be recommended.
Alternatively, the OCWP Reservoir Viability Study identified Cookietown Reservoir in Basin 27 as a viable reservoir site, approximately 30 miles from Basin 26. This reservoir could potentially be used as a suitable supplemental source for members of the Waurika MCD or with additional infrastructure to directly supply Basin 26. Unlike many hot spot basins, Basin 26 is not served by any alternatives in the statewide water conveyance system (OWRB Water Conveyance Alternatives report).
Marginal Water Quality Water Use
The OCWP MQW Work Group Final Report identified areas where there is potential for use of MQW to offset a significant amount of future demand. However, Basin 26 was not found to have significant marginal quality sources or significant potential to offset demand with marginal quality water.
Summary of Supply Options
Short-term to long-term water supply options for Basin 26 include reducing M&I demands through moderately expanded conservation measures, increasing Crop Irrigation efficiency, and continued use of existing non-delineated groundwater sources. Long-term water supply options may include out-of-basin supplies from Waurika MCD or Cookietown Section 4
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Reservoir. However, due to the scale and complexity of these long-term supplies, the cost-effectiveness of these supplies needs to be evaluated against other options on a local level.
4.1.3.3 Summary of Solutions for Basin 34 (Lower North Fork Red River-3)
Basin 34 (Lower North Fork Red River-3) is considered one of the 12 basins with the most significant water supply challenges statewide ("hot spot"). Basin 34 is a surface water hot spot. Surface water issues are mainly due to the Basin's low physical availability of streamflow, lack of available streamflow for new permits, and poor water quality. More detailed information on this basin is available in the OCWP Water Supply Hot Spot Identification and Analysis report. In addition to surface water gaps, alluvial groundwater storage depletions may occur by 2020. Six categories of supply options for mitigating the projected surface water gaps and groundwater storage depletions in Basin 34 are summarized in Table 4-5 and described in the text below.
Table 4-5. Summary of Water Supply Options for Basin 34 Water Supply Option Option Feasibility
Demand Reduction
 Moderately expanded Municipal and Industrial conservation and increase Crop Irrigation efficiency
 Shift to crops with lower water demand
 Short- to long-term solution that may reduce about 50% of surface water gaps and 70% of alluvial groundwater storage depletions
Increased Reliance on Surface Water
 Increased use of surface water supplies, without reservoir storage
 Not feasible
Increased Reliance on Groundwater
 Increased reliance on Elk City bedrock aquifer, instead of increased surface water or alluvial groundwater use
 Increased reliance on North Fork of the Red River alluvial aquifer, instead of increased surface water use
 Elk City bedrock aquifer could be a short to long-term solution
 Increased alluvial aquifer use is not a viable solution
Marginal Quality Water Use
 Use marginal water quality
 No significant sources were identified
Reservoir Storage
 Development of new reservoirs
 Not feasible
Out-of-Basin Supplies
 Statewide water conveyance
 Potential long-term solution
Demand Reduction
Demand reduction could reduce surface water gaps or groundwater storage depletions through expanded permanent conservation measures. Increasing the sprinkler irrigation efficiency in the Crop Irrigation demand sector and implementing moderately expanded conservation measures for the M&I demand sector (Scenario I conservation, as defined in the OCWP Water Demand Forecast Report) could reduce the total demand by 1,970 AFY and reduce the size of the annual surface water gaps by up to 35 percent in 2060 to a value of 1,620 AFY, and alluvial groundwater storage depletions in 2060 by about 60 percent to a value of 190 AFY. This conservation measure could benefit users throughout the basin and should be considered as a short– to long-term water supply option. Section 4
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Substantially expanding M&I conservation measures and shifting from crops with high water demand (e.g., corn for grain and forage crops) to low water demand crops such as sorghum for grain or wheat for grain (Scenario II conservation) could reduce total demand by 2,740 AFY and reduce the size of the surface water gaps in 2060 by an additional 15 percent, to a value of 1,300 AFY. The ability to further reduce surface water gaps with conservation was minimal, as much of the basin's growth in surface water use will be from the Oil and Gas demand sector (for which additional conservation measures were not evaluated). These additional conservation measures could reduce alluvial groundwater storage depletions by an additional 10 percent to a value of 130 AFY. These measures could benefit users throughout the basin and should be considered as a long-term water supply option.
Increased Reliance on Surface Water Supplies
Surface water in the basin is fully allocated, limiting diversions to existing permitted amounts. There is a moderate probability of surface water gaps starting in 2020 for the baseline demand projections. Increased reliance on surface water supplies, which have relatively poor water quality, would increase the size and probability of gaps. Therefore, increased reliance on Basin 34 surface water supplies are not recommended.
Increased Reliance on Groundwater Supplies
Alluvial groundwater supplies are used to meet about 20 percent of the total demand, and bedrock groundwater is used to meet about 30 percent of the total demand, largely for the Crop Irrigation and Oil and Gas demand sectors. The North Fork of the Red River alluvial aquifer underlies the basin in the south (about 15 percent of the overall basin area) and the Elk City bedrock aquifer underlies the basin in the north (about 15 percent of the overall basin area). Due to the hydraulic interconnectivity between alluvial groundwater and surface water, a shift from surface water to alluvial groundwater is not expected to substantially change the maximum storage depletions or surface water gaps in the basin. Increased use of the Elk City bedrock aquifer, with new infrastructure, could provide short- to long-term supplies instead of increasing surface water and alluvial groundwater use, but may cause storage depletions. The resulting storage depletions of up to 710 AFY are minimal relative to the over one million AF of storage in basin 34's portion of the Elk City aquifer.
Reservoir Storage
The OCWP Reservoir Viability Study evaluated the potential for reservoirs throughout the state; no viable sites were identified in Basin 34. Additionally, the basin has been fully allocated. Therefore, development of additional reservoir storage in Basin 34 is not recommended.
Out-of-Basin Supplies
Out-of-basin supplies would be among the most costly of options, but could eliminate the potential for alluvial groundwater depletions and surface water gaps. Elk City is the largest M&I demand in the basin, and currently obtains water from the North Fork of the Red River aquifer in Basin 37. Increased use of this supply could be a short- to long- term water supply option for the city in the future. However, storage depletions from local Section 4
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demand may occur in Basin 37 by 2020 and adversely affect users' yield, water quality, or pumping costs. Additional potential out-of-basin supplies include Mangum Reservoir (Lower Mangum Damsite) and the statewide conveyance system. Mangum Reservoir was identified in the OCWP Reservoir Viability Study report as the nearest viable reservoir, located about 16 miles from the center of Basin 34. With new terminal storage of about 1,800 AF, a 14-inch diameter pipe would be needed to bring out-of-basin supplies at a constant flow rate into Basin 34 for further distribution to users. With no terminal storage and variable flows in the pipeline, a 30-inch diameter pipeline would be needed.
Three alternatives for the statewide water conveyance system to deliver water to the Southwest Region were identified in the OWRB Water Conveyance Alternatives report. All of the alternatives require additional reservoirs, hundreds of miles of piping, canals, and inverted siphons, and many pumping plants. Due to the scale and complexity of developing out-of-basin supplies, the cost-effectiveness of these supplies should be evaluated against other options on a local level. The development of out-of-basin supplies should be considered as a long-term water supply option for users throughout the basin.
Marginal Water Quality Water Use
The OCWP MQW Work Group Final Report identified areas where there is potential for use of MQW to offset a significant amount of future demand. However, Basin 34 was not found to have significant marginal quality sources or significant potential to offset demand with marginal quality water.
Summary of Supply Options
Short-term water supply options for Basin 34 include moderately expanded M&I conservation measures, increased crop irrigation efficiency, increased use of the Elk City aquifer. Long-term water supply options may include increased use of the Elk City aquifer, substantially expanded M&I conservation measures, a shift to crops with a lower water demand, out-of-basin supplies from a new Mangum Reservoir, or the statewide water conveyance system. However, due to the scale and complexity of these long-term supplies, the cost-effectiveness of these supplies should be evaluated against other options on a local level.
4.1.3.4 Summary of Solutions for Basin 36 (Upper North Fork Red River-1)
Basin 36 (Upper North Fork Red River-1) is an alluvial groundwater hot spot, where storage depletions are expected to provide water supply challenges based on the overall size of the depletions and for the rate of storage depletions relative to the amount of groundwater storage in the North Fork of the Red River aquifer. More detailed information on this basin is available in the OCWP Water Supply Hot Spot Identification and Analysis report and the Southwest Watershed Region Planning Report. In addition to alluvial groundwater storage depletions, surface water gaps may occur by 2050. Six categories of supply options for mitigating the projected surface water gaps and groundwater storage depletions in Basin 36 are summarized in Table 4-6 and described in the text below. Section 4
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Table 4-6. Summary of Water Supply Options for Basin 36 Water Supply Option Option Feasibility
Demand Reduction
 Increased Crop Irrigation efficiency
 Shift to crops with lower water demand
 Short- to long-term solution that could eliminate surface water gaps and reduce 2060 groundwater depletions by 15% to 50%
Increased Reliance on Surface Water
 Increased use of surface water supplies, without reservoir storage
 Not feasible
Increased Reliance on Groundwater
 Increased reliance on North Fork of Red River aquifer
 Short -term solution; may not provide consistent or cost-effective supplies in the long term
Marginal Quality Water Use
 Use brackish groundwater sources for Crop Irrigation
 Potential long-term applicability for irrigation of certain crops
Reservoir Storage
 Development of new reservoirs
 Not feasible
Out-of-Basin Supplies
 Mangum Reservoir or Statewide Water Conveyance
 Potential long-term solution
Demand Reduction
Demand reduction could reduce surface water gaps or groundwater storage depletions through expanded permanent conservation measures. Increasing the sprinkler irrigation efficiency in the Crop Irrigation demand (Scenario I conservation, as defined in the OCWP Water Demand Forecast Report) could reduce the demand by 400 AFY. In Kiowa County, Scenario I conservation measures would also include increasing the efficiency of surface irrigation systems to 80 percent and shifting 10 percent of the land irrigated by surface irrigation to micro-irrigation. These moderately expanded conservation measures may reduce the size of the alluvial groundwater storage depletions in 2060 by about 15 percent, to a value of 2,170 AFY. However, these additional conservation measures are not expected to significantly decrease surface water gaps. These conservation measures could benefit users throughout the basin and should be considered as a short– to long-term water supply option.
Current crops are predominantly forage crops and wheat for grain. A shift from crops with high water demand (e.g., forage crops) to low water demand crops such as sorghum for grain or wheat for grain (Scenario II conservation) could reduce demand by 1,260 AFY and eliminate surface water gaps and reduce alluvial groundwater storage depletions in 2060 by about 50 percent, to a value of 1,360 AFY. This measure could benefit users throughout the basin and should be considered as a long-term water supply option. Additional conservation measures in the M&I demand sector may help reduce the adverse effects of localized storage depletions, but will not have a significant impact basin wide, because the basin's M&I demand is significantly less than that of the Crop Irrigation demand sector.
Increased Reliance on Surface Water Supplies
Surface water in the basin is fully allocated, limiting diversions to existing permitted amounts. There is a very high probability of surface water gaps starting in 2050 for the baseline demand projections. Increased reliance on surface water use, if permits could be issued, would increase the size and probability of these gaps. Therefore, increased reliance on Basin 36 surface water supplies is not recommended. Section 4
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Increased Reliance on Groundwater Supplies
Alluvial groundwater storage depletions of up to 1,000 AF/month are expected to occur July and August of almost every summer by 2060. These storage depletions are small in size on a basin scale relative to the storage in the North Fork of the Red River alluvial aquifer, which underlies about 60 percent of the basin. Due to the relatively small projected growth in surface water use, new surface water users could instead be supplied by the North Fork of the Red River aquifer with minimal (10 AFY) increases in projected storage depletions. Due to the alluvial aquifer's connection to river flows and precipitation, aquifer levels may fluctuate naturally, due to prolonged periods of drought or above-average precipitation. While increased use of alluvial water would not substantially increase depletions of stored water, during periods of drought the effect of these storage depletions may be intensified. These localized storage depletions may adversely affect users' yields, water quality, and pumping costs. Therefore, the development of additional alluvial groundwater supplies to meet the growth in surface water or alluvial groundwater demand should be considered a short-term water supply option. Over a long-term period, demand reduction and other supply options may provide more consistent supplies and may be more cost-effective.
Reservoir Storage
The OCWP Reservoir Viability Study evaluated the potential for reservoirs throughout the state; no viable sites were identified in this basin. The basin is fully allocated for permits and any new reservoirs could not impact the yield of Lugert-Altus Reservoir, which is located at the basin outlet. Therefore, development of additional reservoir storage in Basin 36 is not recommended.
Out-of-Basin Supplies
Out-of-basin supplies would be among the most costly of options, but could eliminate the potential for alluvial groundwater depletions and surface water gaps. Potential out-of-basin supplies include Mangum Reservoir (Lower Mangum Damsite) and the statewide conveyance system. Mangum Reservoir was identified in the OCWP Reservoir Viability Study report as the nearest viable reservoir, located about 16 miles from the center of Basin 36. With new terminal storage of about 1,800 AF, a 14-inch diameter pipe would be needed to bring out-of-basin supplies at a constant flow rate into Basin 36 for further distribution to users. With no terminal storage and variable flows in the pipeline, a 30-inch diameter pipeline would be needed.
Three alternatives for the statewide water conveyance system to deliver water to the Southwest Region were identified in the OWRB Water Conveyance Alternatives report. All of the alternatives require additional reservoirs, hundreds of miles of piping, canals, and inverted siphons, and many pumping plants. Due to the scale and complexity of developing out-of-basin supplies, the cost-effectiveness of these supplies should be evaluated against other options on a local level. The development of out-of-basin supplies should be considered as a long-term water supply option for users throughout the basin. Section 4
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Marginal Water Quality Water Use
The OCWP MQW Work Group Final Report identified areas where there is potential for use of MQW to offset a significant amount of future demand. Basin 36 was found to have significant brackish marginal quality groundwater sources that could be used to meet Crop Irrigation demand. These groundwater sources are typically deeper than fresh water aquifers and not associated with delineated aquifers. Crops that are among the most salinity-tolerant include barley and wheat. Brackish water supplies are those that have between 1,000 milligrams per liter (mg/L) and 35,000 mg/L TDS. OWRB does not have regulatory authority to permit withdrawals of groundwater with TDS concentrations greater than 5,000 mg/L. The U.S. Geological Survey (USGS) is currently conducting a 3-year study (to be completed in 2012) to delineate and assess saline groundwater supplies (including brackish groundwater) in Oklahoma and surrounding states. Brackish groundwater underlies the entire basin and should be evaluated as a potential short– to long-term water supply option. However, these supplies will likely be less preferable than supplies from the lower-salinity North Fork of the Red River aquifer.
Summary of Supply Options
Short-term water supply options for Basin 36 include increasing crop irrigation efficiency and increasing use of the North Fork of the Red River alluvial aquifer. Long-term water supply options may include a shift to crops with lower water demand, out-of-basin supplies from a new Mangum Reservoir, or the statewide water conveyance system. However, due to the scale and complexity of these long-term supplies, the cost-effectiveness of these supplies should be evaluated against other options on a local level.
4.1.3.5 Summary of Solutions for Basin 38 (Salt Fork Red River-1)
Basin 38 (Salt Fork Red River-1) is an alluvial groundwater and bedrock groundwater hot spot. The basin is mainly challenged by the rate of storage depletions in the Blaine and North Fork of the Red River aquifers. However, the overall size of storage depletions to these aquifers may also create significant water supply challenges. More detailed information on this basin is available in the OCWP Water Supply Hot Spot Identification and Analysis report and the Southwest Watershed Region Planning Report. In addition to alluvial groundwater storage depletions, surface water gaps and bedrock groundwater storage depletions may occur by 2060. Six categories of supply options for mitigating surface water gaps and groundwater storage depletions in Basin 38 are summarized in Table 4-7 and described in the text below. Section 4
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Table 4-7 Summary of Water Supply Options for Basin 38 Water Supply Option Option Feasibility
Demand Reduction
 Increased Crop Irrigation efficiency
 Short- to long-term solution that may eliminate surface water gaps and groundwater depletions
Increased Reliance on Surface Water
 Increased use of surface water supplies, without reservoir storage
 Not feasible
Increased Reliance on Groundwater
 Increased reliance on the Blaine aquifer instead of increased surface water and alluvial groundwater use
 Short-term solution; not sustainable and may not be cost-effective in the long term
Marginal Quality Water Use
 Use brackish groundwater sources for Crop Irrigation
 Potential long-term applicability for irrigation of certain crops
Reservoir Storage
 Development of new reservoirs
��� Not feasible
Out-of-Basin Supplies
 Mangum Reservoir or Statewide Water Conveyance
 Potential long-term solution
Demand Reduction
Demand reduction could reduce surface water gaps or groundwater storage depletions through expanded permanent conservation measures. Increasing the sprinkler irrigation efficiency in the Crop Irrigation demand, increasing the efficiency of surface irrigation systems to 80 percent, and shifting 10 percent of the land irrigated by surface irrigation to micro-irrigation (Scenario I conservation, as defined in the OCWP Water Demand Forecast Report) could reduce the demand by 15,600 AFY. These moderately expanded conservation measures may eliminate the alluvial groundwater storage depletions, surface water gaps, and bedrock groundwater storage depletions. These conservation measures could benefit users throughout the basins and should be considered as a short– to long-term water supply option. Additional conservation measures in the M&I demand sector may help reduce the storage depletions and gaps, but will not have a significant impact basin wide, because the basin's M&I demand is significantly less than that of the Crop Irrigation demand sector.
Increased Reliance on Surface Water Supplies
The primary sources of water (62 percent of the total demand) in this basin are surface water and out-of-basin supplies from the Lugert-Altus Irrigation District, which is not expected to provide supplies for new irrigators in the future. Therefore, additional water supplies will be needed from the Salt Fork of the Red River or from alluvial or bedrock aquifers. Unlike many basins in the Southwest Region, use of surface water to meet local demand in Basin 38 through 2060 is not expected to be limited by the availability of permits. However, there is a low to moderate probability of surface water gaps starting in 2020 for the baseline demand projections. Increased reliance on surface water use would increase the size and probability of these gaps. Therefore, increased reliance on Basin 38 surface water supplies is not recommended.
Increased Reliance on Groundwater Supplies
Currently, about 25 percent of the total demand is met from the Blaine aquifer and about 13 percent is met from non-delineated minor aquifers along the Salt Fork of the Red River and Turkey Creek. Under baseline demand conditions, storage depletions in alluvial and Section 4
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bedrock aquifers are expected to increase due largely to the growth in Crop Irrigation demand, which may cause adverse effects in localized areas. The projected growth in surface water and alluvial groundwater use could instead be supplied by the Blaine bedrock aquifer, but would result in large (6,900 AFY) increases in projected bedrock groundwater storage depletions. Additionally, the Blaine aquifer only underlies the western half of the basin. The development of additional bedrock groundwater supplies should be considered a short-term water supply option. Over the long term, the increased depletions of stored water would likely lead to decreased well yields and increased pumping costs, making demand reduction and other supply options more sustainable and cost-effective. The Blaine aquifer supplies may be obtained from cavities, solution channels, and fractures in the rock. Increased storage depletions could create changes in these features that may intensify the effect of storage depletions on a local level.
Artificial recharge (AR) has been conducted in the Blaine aquifer since the late 1960s. In 1997, a groundwater recharge study was performed to determine the effectiveness of AR wells in Basins 40 and 41. The study found that on average, one recharge well could recharge the aquifer at a rate of about half that of the water withdrawal from an irrigation well (recharge of 70 AFY compared to average annual pumping of 142 AFY per irrigation well). Increased use of this practice could be effective at reducing the effects of localized storage depletions in Basin 38.
The majority of current alluvial groundwater rights are in non-delineated minor aquifers; therefore, the typical yields, volume of stored water, and water quality are unknown. Increased reliance on these supplies is not recommended without site-specific information.
Reservoir Storage
The development of reservoir storage in Basin 42 does not appear to be feasible. The OCWP Reservoir Viability Study evaluated the potential for reservoirs throughout the state; no viable sites were identified in Basin 42. Basin-level evaluations in the Southwest Watershed Planning Region Report indicate that if a suitable site could be identified, a reservoir with 8,900 AF of storage at the basin outlet and new conveyance infrastructure could meet the basin's entire growth in demand from 2010 to 2060. However, a detailed evaluation of the feasibility of any reservoir would be needed and should include consideration of existing land ownership, costs, geology, water quality, and permitting/ compact obligations.
Out-of-Basin Supplies
Out-of-basin supplies would be among the most costly of options, but could eliminate the potential for surface water gaps and groundwater depletions. There are substantial existing out-of-basin supplies from the Lugert-Altus Irrigation District; however, the Irrigation District is not expected to provide supplies for new irrigators in the future.
The development of additional out-of-basin supplies should be considered as a long-term water supply option for users throughout the basin. However, due to the scale and complexity of developing out-of-basin supplies, the cost-effectiveness of these supplies Section 4
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needs to be evaluated against other options on a local level. Potential out-of-basin supplies include Mangum Reservoir (Lower Mangum Damsite) and the statewide conveyance system. Mangum Reservoir was identified in the OCWP Reservoir Viability Study report as the nearest viable reservoir, located about 11 miles from the center of Basin 38. With new terminal storage of about 7,000 AF, a 30-inch diameter pipe would be needed to bring out-of-basin supplies at a constant flow rate into Basin 38 for further distribution to users and eliminate gaps and storage depletions. With no terminal storage and variable flows in the pipeline, a 54-inch diameter pipeline would be needed.
Three alternatives for the statewide water conveyance system to deliver water to the Southwest Region were identified in the OWRB Water Conveyance Alternatives report. All of the alternatives require additional reservoirs, hundreds of miles of piping, canals, and inverted siphons, and many pumping plants. This option should therefore be considered a long-term option, and may be best implemented in conjunction with other local and regional supply options.
Marginal Water Quality Water Use
The OCWP MQW Work Group Final Report identified areas where there is potential for use of MQW to offset a significant amount of future demand. Basin 38 was found to have significant brackish marginal quality groundwater sources that could be used to meet Crop Irrigation demand. These groundwater sources are typically deeper than fresh water aquifers and not associated with delineated aquifers, such as the Blaine aquifer. Crops that are among the most salinity-tolerant include barley and wheat. Brackish water supplies are those that have between 1,000 mg/L and 35,000 mg/L TDS. OWRB does not have regulatory authority to permit withdrawals of groundwater with TDS concentrations greater than 5,000 mg/L. The USGS is currently conducting a 3-year study (to be completed in 2012) to delineate and assess saline groundwater supplies (including brackish groundwater) in Oklahoma and surrounding states. Brackish groundwater underlies the entire basin and should be evaluated as a potential short– to long-term water supply option. However, these supplies will likely be less preferable than supplies from the lower-salinity North Fork of the Red River aquifer.
Summary of Supply Options
Short-term water supply options for Basin 38 include increasing crop irrigation efficiency and increasing use of the Blaine aquifer. Long-term water supply options may include out-of-basin supplies from a new Mangum Reservoir, or the statewide water conveyance system. However, due to the scale and complexity of these long-term supplies, the cost-effectiveness of these supplies should be evaluated against other options on a local level.
4.1.3.6 – Summary of Solutions for Basin 40 (Prairie Dog Town Fork Red River-1) and Basin 41 (Prairie Dog Town Fork Red River-2)
Basin 40 (Prairie Dog Town Fork Red River-1) and Basin 41 (Prairie Dog Town Fork Red River-2) represent the entire watershed of Sand Creek in Oklahoma and have very similar water supply needs and resources; therefore, they were evaluated as a single hot spot. Basin 40 is a surface water and bedrock groundwater hot spot, and Basin 41 is a bedrock Section 4
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groundwater hot spot. Surface water issues are mainly due to low physical availability of streamflow, lack of available streamflow for new permits, and relatively poor water quality. Both basins are challenged by the overall size of storage depletions and for the rate of storage depletions relative to the amount of groundwater storage in the Blaine aquifer. Shortages in these basins are in large part driven by the significant seasonal demand of the area's Crop Irrigation practices. More detailed information on this basin is available in the OCWP Water Supply Hot Spot Identification and Analysis report and the Southwest Watershed Region Planning Report. In addition to the challenges noted above, surface water gaps may occur in Basin 41 by 2030 and alluvial groundwater storage depletions may occur by 2020 in both Basin 40 and Basin 41. Six categories of supply options for mitigating surface water gaps and groundwater storage depletions in Basins 40 and 41 are summarized in Table 4-8 and described in the text below.
Table 4-8. Summary of Water Supply Options for Basins 40 and 41 Water Supply Option Option Feasibility
Demand Reduction
 Increased Crop Irrigation efficiency
 Shift to crops with lower water demand
 Short- to long-term solution that may reduce surface water gaps and alluvial groundwater storage depletions by about 90% and eliminate bedrock storage depletions.
Increased Reliance on Surface Water
 Increased use of surface water supplies, without reservoir storage
 Not feasible
Increased Reliance on Groundwater
 Increased reliance on the Blaine bedrock aquifer
 Short-term solution; not sustainable and may not be cost-effective in the long term
Marginal Quality Water Use
 Use brackish groundwater sources for Crop Irrigation
 Potential long-term applicability for irrigation of certain crops
Reservoir Storage
 Development of new reservoirs
 Not feasible
Out-of-Basin Supplies
 Mangum Reservoir or Statewide Water Conveyance
 Potential long-term solution
Demand Reduction
Demand reduction could reduce surface water gaps or groundwater storage depletions through expanded permanent conservation measures. Increasing the sprinkler irrigation efficiency in the Crop Irrigation demand, increasing the efficiency of surface irrigation systems to 80 percent, and shifting 10 percent of the land irrigated by surface irrigation to micro-irrigation (Scenario I conservation, as defined in the OCWP Water Demand Forecast Report) could reduce the two basins' combined demand by 8,630 AFY. These moderately expanded conservation measures may reduce the size of the combined annual surface water gaps in 2060 by about 60 percent, to a value of 160 AFY. It would also reduce the combined alluvial groundwater storage depletions in 2060 by about 95 percent to a value of 90 AFY, and eliminate bedrock groundwater depletions. These conservation measures could benefit users throughout the Basins and should be considered as a short– to long-term water supply option.
Current crops are predominantly cotton, wheat, forage crops, and sorghum. A shift from crops with high water demand (e.g., forage crops) to low water demand crops such as sorghum for grain or wheat for grain (Scenario II conservation) could reduce demand by an Section 4
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additional 1,750 AFY. This additional demand reduction could decrease the combined surface water gaps by 5 percent, to a value of 50 AFY and the combined alluvial groundwater storage depletions by an additional 3 percent, to a value of 30 AFY. This conservation measure may be a feasible long-term water supply option for specific users. Additional conservation measures in the M&I demand sector may help reduce the adverse effects of localized storage depletions, but will not have a significant impact basin wide, because the basins' M&I demand is significantly less than that of the Crop Irrigation demand sector.
Increased Reliance on Surface Water Supplies
Surface water in these basins is fully allocated, limiting diversions to existing permitted amounts. There is a moderate to high probability of surface water gaps starting in 2020 for Basin 40 and 2030 for Basin 41 for the baseline demand projections. Increased reliance on surface water use, if permits could be issued, would increase the size and probability of these gaps. Therefore, increased reliance on Basin 40 and 41 surface water supplies is not recommended.
Increased Reliance on Groundwater Supplies
Under baseline demand, storage depletions of the Blaine aquifer and of non-delineated minor aquifers along the Red River and Sandy Creek are expected to increase due largely to the growth in Crop Irrigation demand. The projected growth in surface water and alluvial groundwater use could instead be supplied by the Blaine aquifer, which would result in about 1.5 times the projected bedrock groundwater storage depletions under the baseline scenario. The development of additional bedrock groundwater supplies should be considered a short-term water supply option. Over the long term, the increased depletions of stored water would likely lead to decreased well yields and increased pumping costs, making demand reduction and other supply options more sustainable and cost-effective. The Blaine aquifer supplies may be obtained from cavities, solution channels, and fractures in the rock. Increased storage depletions could create changes in these features that may intensify the effect of storage depletions on a local level.
AR has been conducted in the Blaine aquifer since the late 1960s. In 1997, a groundwater recharge study was performed to determine the effectiveness of AR wells in these basins. The study found that on average, one recharge well could recharge the aquifer at a rate of about half that of the water withdrawal from an irrigation well (recharge of 70 AFY compared to average annual pumping of 142 AFY per irrigation well). Increased use of this practice could be effective at reducing the effects of localized storage depletions in Basins 40 and 41.
Reservoir Storage
The development of reservoir storage in Basins 40 and 41 are does not appear to be feasible. The OCWP Reservoir Viability Study evaluated the potential for reservoirs throughout the state; no viable sites were identified in these basins. In addition, the basin is already fully allocated for surface water permits, making this supply option infeasible. Section 4
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Out-of-Basin Supplies
Out-of-basin supplies would be among the most costly of options, but could eliminate the potential for surface water gaps and groundwater depletions. The development of out-of-basin supplies should be considered as a long-term water supply option for users throughout the basins. However, due to the scale and complexity of developing out-of-basin supplies, the cost-effectiveness of these supplies needs to be evaluated against other options on a local level. Potential out-of-basin supplies include Mangum Reservoir (Lower Mangum Damsite) and the statewide conveyance system. Mangum Reservoir was identified in the OCWP Reservoir Viability Study report as the nearest viable reservoir, located about 25 miles from the center of Basins 40 and 41. With new terminal storage of about 1,400 AF, a 12-inch diameter pipe would be needed to bring out-of-basin supplies at a constant rate into Basin 40 for further distribution to users and eliminate gaps and storage depletions. With no terminal storage and variable flows in the pipeline, a 24-inch diameter pipeline would be needed. With new terminal storage of about 3,000 AF, a 16-inch diameter pipe would be needed to bring out-of-basin supplies at a constant rate into Basin 41 for further distribution to users and eliminate gaps and storage depletions. With no terminal storage and variable flows in the pipeline, a 36-inch diameter pipeline would be needed.
Three alternatives for the statewide water conveyance system to deliver water to the Southwest Region were identified in the OWRB Water Conveyance Alternatives report. All of the alternatives require additional reservoirs, hundreds of miles of piping, canals, and inverted siphons, and many pumping plants. This option should therefore be considered a long-term option, and may be best implemented in conjunction with other local and regional supply options.
Marginal Water Quality Water Use
The OCWP MQW Work Group Final Report identified areas where there is potential for use of MQW to offset a significant amount of future demand. Basins 40 and 41 were found to have significant brackish marginal quality groundwater sources that could be used to meet Crop Irrigation demand. These groundwater sources are typically deeper than fresh water aquifers and not associated with delineated aquifers, such as the Blaine aquifer. Crops that are among the most salinity-tolerant include barley and wheat. Brackish water supplies are those that have between 1,000 mg/L and 35,000 mg/L TDS. OWRB does not have regulatory authority to permit withdrawals of groundwater with TDS concentrations greater than 5,000 mg/L. The USGS is currently conducting a 3-year study (to be completed in 2012) to delineate and assess saline groundwater supplies (including brackish groundwater) in Oklahoma and surrounding states. Brackish groundwater underlies the entire basin and should be evaluated as a potential short– to long-term water supply option. However, these supplies will likely be less preferable than supplies from the shallower Blaine aquifer.
Summary of Supply Options
Short-term water supply options for Basins 40 and 41 include increasing crop irrigation efficiency and increasing use of the Blaine bedrock aquifer. Long-term water supply Section 4
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options may include a shift to crops with lower water demand, out-of-basin supplies from a new Mangum Reservoir, or the statewide water conveyance system. However, due to the scale and complexity of these long-term supplies, the cost-effectiveness of these supplies should be evaluated against other options on a local level.
4.1.3.7 Summary of Solutions for Basin 42 (Elm Fork of the Red River-3)
Basin 42 (Elm Fork of the Red River-3) is a hot spot for surface water and alluvial groundwater supplies. Surface water issues are mainly associated with the basin's low physical availability of streamflow and relatively poor water quality. The basin is also challenged by the overall size of storage depletions and for the rate of storage depletions relative to the amount of groundwater storage in the North Fork of the Red River aquifer. Shortages in the basin are in large part driven by the significant seasonal demand of the area's Crop Irrigation practices. More detailed information on this basin is available in the OCWP Water Supply Hot Spot Identification and Analysis report and the Southwest Watershed Region Planning Report. In addition to the challenges noted above, bedrock groundwater storage depletions are projected to occur by 2020. Six categories of supply options for mitigating surface water gaps and groundwater storage depletions in Basin 42 are summarized in Table 4-9 and described in the text below.
Table 4-9. Summary of Water Supply Options for Basin 42 Water Supply Option Option Feasibility
Demand Reduction
 Increased Crop Irrigation efficiency
 Shift to crops with lower water demand
 Short- to long-term solution that could reduce 2060 groundwater depletions by 10% to 37%
Increased Reliance on Surface Water
 Increased use of surface water supplies, without reservoir storage
 Not feasible
Increased Reliance on Groundwater
 Increased reliance on the North Canadian River alluvial aquifer instead of increased surface water and bedrock groundwater use
 Short-term solution; may not provide consistent or cost-effective supplies in the long term
Marginal Quality Water Use
 Use brackish groundwater sources for Crop Irrigation
 Potential long-term applicability for irrigation of certain crops
Reservoir Storage
 Development of new reservoirs
 Not feasible
Out-of-Basin Supplies
 Mangum Reservoir or Statewide Water Conveyance
 Potential long-term solution
Demand Reduction
Demand reduction could reduce surface water gaps or groundwater storage depletions through expanded permanent conservation measures. Increasing the sprinkler irrigation efficiency in the Crop Irrigation demand (Scenario I conservation, as defined in the OCWP Water Demand Forecast Report) could reduce the total demand by 400 AFY and reduce the size of the annual alluvial groundwater storage depletions in 2060 by about 10 percent, to a value of 2,400 AFY and the size of annual surface water gaps in 2060 by about 15 percent, to a value of 230 AFY. This conservation measure could benefit users throughout the basin and should be considered as a short– to long-term water supply option. Section 4
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Current crops are predominantly forage crops and peanuts for nuts, and to a lesser extent, corn for grain and other crops. A shift from crops with high water demand (e.g., corn for grain and forage crops) to low water demand crops such as sorghum for grain or wheat for grain (Scenario II conservation) could reduce demand by 1,360 AFY and reduce the size of the annual groundwater storage depletions and surface water gaps by about 37 percent, to a value of 1,680 AFY for alluvial groundwater storage depletions and to a value of 170 AFY for surface water gaps. This measure could benefit users throughout the basin and should be considered as a long-term water supply option. Additional conservation measures in the M&I demand sector may help reduce the adverse effects of localized storage depletions, but will not have a significant impact basin wide, because the basin's M&I demand is significantly less than that of the Crop Irrigation demand sector.
Increased Reliance on Surface Water Supplies
Unlike many basins in the Southwest Region, use of surface water to meet local demand in Basin 42 through 2060 is not expected to be limited by the availability of permits. However, there is a moderate to high probability of surface water gaps starting in 2040 for the baseline demand projections. Increased reliance on surface water use would increase the size and probability of these gaps. Therefore, increased reliance on Basin 42 surface water supplies is not recommended.
Increased Reliance on Groundwater Supplies
The primary source of water (71 percent of the total demand) in this basin is alluvial groundwater from the North Canadian River alluvial aquifer. Under baseline demand, storage depletions are expected to occur in the North Canadian River and in non-delineated minor aquifers in terrace deposits of the Salt Fork of the Red River, due largely to the growth in Crop Irrigation demand. The projected growth in surface water and bedrock groundwater use could instead be supplied by the North Canadian River aquifer, which would result in moderate (510 AFY) increases in projected alluvial groundwater storage depletions. Due to the alluvial aquifer's connection to river flows and precipitation, aquifer levels may to fluctuate naturally, due to prolonged periods of drought or above-average precipitation. While increased use of alluvial water would not substantially increase depletions of stored water, during periods of drought the effect of these storage depletions may be intensified. These localized storage depletions may adversely affect users' yields, water quality, and pumping costs. Therefore, the development of additional alluvial groundwater supplies to meet the growth in surface water or alluvial groundwater demand should be considered a short-term water supply option. Over a long-term period, demand reduction and other supply options may provide more consistent supplies and may be more cost-effective.
Bedrock groundwater supplies are from non-delineated minor aquifers; therefore, increased reliance on these supplies is not recommended without site-specific information. Section 4
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Reservoir Storage
The development of reservoir storage in Basin 42 does not appear to be feasible. The OCWP Reservoir Viability Study evaluated the potential for reservoirs throughout the state; no viable sites were identified in Basin 42. Basin-level evaluations in the Southwest Watershed Planning Region Report indicate that if a suitable site could be identified, a reservoir with 3,900 AF of storage at the basin outlet and new conveyance infrastructure could meet the basin's entire growth in demand from 2010 to 2060. However, a detailed evaluation of the feasibility of any reservoir would be needed and should include consideration of existing land ownership, costs, geology, water quality, and permitting/ compact obligations.
Out-of-Basin Supplies
Out-of-basin supplies would be among the most costly of options, but could eliminate the potential for surface water gaps and groundwater depletions. The development of out-of-basin supplies should be considered as a long-term water supply option for users throughout the basin. However, due to the scale and complexity of developing out-of-basin supplies, the cost-effectiveness of these supplies needs to be evaluated against other options on a local level. Potential out-of-basin supplies include Mangum Reservoir (Lower Mangum Damsite) and the statewide conveyance system. Mangum Reservoir was identified in the OCWP Reservoir Viability Study report as the nearest viable reservoir site to the basin, although it would be 90 miles or more away from the majority of users in Basin 42. With new terminal storage of about 3,000 AF, a 16-inch diameter pipe would be needed to bring out-of-basin supplies at a constant flow rate into Basin 42 for further distribution to users. With no terminal storage and variable flows in the pipeline, a 30-inch diameter pipeline would be needed.
Three alternatives for the statewide water conveyance system to deliver water to the Southwest Region were identified in the OWRB Water Conveyance Alternatives report. All of the alternatives require additional reservoirs, hundreds of miles of piping, canals, and inverted siphons, and many pumping plants. This option should therefore be considered a long-term option, and may be best implemented in conjunction with other local and regional supply options.
Marginal Water Quality Water Use
The OCWP MQW Work Group Final Report identified areas where there is potential for use of MQW to offset a significant amount of future demand. Basin 42 was found to have significant brackish marginal quality groundwater sources that could be used to meet Crop Irrigation demand. These groundwater sources are typically deeper than fresh water aquifers and not associated with delineated aquifers. Crops that are among the most salinity-tolerant include barley and wheat. Brackish water supplies are those that have between 1,000 mg/L and 35,000 mg/L TDS. OWRB does not have regulatory authority to permit withdrawals of groundwater with TDS concentrations greater than 5,000 mg/L. The USGS is currently conducting a 3-year study (to be completed in 2012) to delineate and assess saline groundwater supplies (including brackish groundwater) in Oklahoma and surrounding states. Brackish groundwater underlies the entire basin and should be Section 4
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evaluated as a potential short– to long-term water supply option. However, these supplies will likely be less preferable than supplies from the lower-salinity North Fork of the Red River aquifer.
Summary of Supply Options
Short-term water supply options for Basin 42 include increasing crop irrigation efficiency and increased reliance on the North Fork of the Red River alluvial aquifer to meet the growth in surface water and alluvial groundwater demand. Long-term water supply options may include a shift to crops with lower water demand and out-of-basin supplies from a new Mangum Reservoir or the statewide water conveyance system. However, due to the scale and complexity of these long-term supplies, the cost-effectiveness of these supplies should be evaluated against other options on a local level.
4.1.3.8 Summary of Solutions for Basin 51 (Middle North Canadian River)
Basin 51 (Middle North Canadian River) is a surface water and alluvial groundwater hot spot. Surface water issues are mainly associated with the basin’s low physical availability of streamflow, lack of available streamflow for new permits, and to a lesser extent its fair water quality. Storage depletions are expected to present water supply challenges based on the overall size of the depletions and for the rate of those depletions relative to the amount of groundwater storage in the North Canadian River and Canadian River alluvial aquifers. More detailed information on this basin is available in the OCWP Water Supply Hot Spot Identification and Analysis report and the Central Watershed Region Planning Report. In addition to surface water gaps and alluvial groundwater storage depletions, bedrock groundwater storage depletions may occur by 2020. Six categories of supply options for mitigating the projected surface water gaps and groundwater storage depletions in Basin 51 are summarized in Table 4-10 and described in the text below.
Table 4-10 Summary of Water Supply Options for Basin 51 Water Supply Option Option Feasibility
Demand Reduction
 Moderately expanded conservation for Municipal and Industrial sector and increased Crop Irrigation efficiency
 Substantially expanded Municipal and Industrial conservation
 Short- to long-term solution that may significantly reduce or eliminate surface water gaps and groundwater storage depletions
Increased Reliance on Surface Water
 Increased use of surface water supplies, without reservoir storage
 Not feasible
Increased Reliance on Groundwater
 Increased reliance on the North Canadian River and Canadian River alluvial aquifers
 Short-term solution; may not be consistent or cost-effective in the long term
Marginal Quality Water Use
 Use brackish groundwater sources for Crop Irrigation
 Use brackish groundwater sources for Livestock or, with treatment, for M&I demand
Reservoir Storage
 Development of new reservoirs
 Not feasible
Out-of-Basin Supplies
 Potential reservoir sites in other basins may provide supplies. Terminal storage in-basin could reduce the size of the pipe needed to convey supplies in basin.
 Potential long-term solutions Section 4
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Demand Reduction
Demand reduction could reduce surface water gaps and groundwater storage depletions through expanded permanent conservation measures. Increasing the sprinkler irrigation efficiency in the Crop Irrigation demand sector and moderately expanded conservation measures for the M&I demand sector (Scenario I conservation, as defined in the OCWP Water Demand Forecast Report) could together reduce the demand by 3,570 AFY and reduce the size of the annual surface water gaps by up to about 80 percent in 2060, to a value of 340 AFY. It would also reduce 2060 alluvial groundwater storage depletions by about 70 percent, to a value of 770 AFY, and 2060 bedrock groundwater storage depletions by about 80 percent, to a value of 20 AFY. Moderately expanded conservation measures could benefit users throughout the basin and should be considered as a short– to long-term water supply option.
Surface water gaps could be nearly eliminated (an overall reduction of 97 percent) to a value of 50 AFY with a shift from crops with high water demand (e.g., corn for grain and forage crops) to low water demand crops such as sorghum for grain or wheat for grain and substantially expanded conservation measures for the M&I demand sector (Scenario II conservation, as defined in the OCWP Water Demand Forecast Report). M&I Scenario II conservation measures would include implementation of a high efficiency plumbing code ordinance, increased water conservation education, and widespread adoption of conservation water rates. These substantially expanded conservation measures would reduce alluvial groundwater storage depletions by an additional 23 percent, to a value of 110 AFY, and would eliminate bedrock groundwater storage depletions. These measures could benefit users throughout the basin and should be considered as a long-term water supply option.
Increased Reliance on Surface Water Supplies
Surface water in the basin is fully allocated, limiting diversions to existing permitted amounts. There is a high probability of surface water gaps in Basin 51 starting in 2020 for the baseline demand projections. Increased reliance on surface water use, if permits could be issued, would increase these gaps. Therefore, increased reliance on Basin 51 surface water supplies is not recommended.
Increased Reliance on Groundwater Supplies
The primary source of water (59 percent of the total demand) in this basin is alluvial groundwater from the North Canadian River and Canadian River alluvial aquifers. Under baseline demand, storage depletions are expected to occur in these aquifers due largely to the growth in M&I and Thermoelectric Power demand sectors. The projected growth in surface water use and bedrock groundwater use could instead be supplied by the North Canadian River or Canadian River alluvial aquifers, which would result in moderate (520 AFY) increases in projected alluvial groundwater storage depletions. Due to the alluvial aquifers’ connection to river flows and precipitation, aquifer levels may fluctuate naturally due to prolonged periods of drought or above-average precipitation. While increased use of alluvial water would not substantially increase depletions of stored water, during periods of drought the effect of these storage depletions may be intensified. These Section 4
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localized storage depletions may adversely affect users’ yields, water quality, and pumping costs, and may also affect surface water flows. Therefore, the development of additional alluvial groundwater supplies instead of increased surface water or alluvial groundwater demand should be considered a short-term water supply option. Over a long-term period, demand reduction and other supply options may provide more consistent supplies and may be more cost-effective.
Bedrock groundwater supplies are from the El Reno minor aquifer; therefore, increased reliance on these supplies is not recommended without site-specific information.
Reservoir Storage
The development of reservoir storage in Basin 51 does not appear to be feasible. The OCWP Reservoir Viability Study evaluated the potential for reservoirs throughout the state; no viable sites were identified in Basin 51. In addition, the basin is already fully allocated for surface water permits, making this supply option infeasible.
Out-of-Basin Supplies
Basin 51 is fully allocated for surface water permits in part due to the permitted use of North Canadian River flows to supply a portion of the central Oklahoma regional demand. Municipal water providers in the southeast portion of Basin 51 may have additional opportunities to form regional partnerships with metro-area providers to share water supplies and infrastructure on a wholesale or retail basis through regional system interconnectivity.
Alternatively, users in Basin 51 could secure new out-of-basin supplies from other basins to meet their future water needs and mitigate the potential for shortages. To supply the entire Basin 51 increase in M&I demand from 2010 to 2060, an additional 3,280 AFY of out-of-basin supplies would be required. With new terminal storage of 400 AF, a 14-inch diameter pipe would be needed to bring out-of-basin supplies at a constant flow rate into Basin 51 for further distribution to users. With no terminal storage and variable flows in the pipeline, an 18-inch diameter pipeline would also be recommended. Regional partnerships or increased use of out-of-basin supplies could benefit M&I users throughout the basin and should be considered as a short– to long-term water supply option.
The OCWP Reservoir Viability Study identified four potentially viable reservoirs near Basin 51. Potential out-of-basin supplies include five potential, not yet constructed, reservoirs. Hennessey Reservoir, Hydro Reservoir, Navina Reservoir, Sheridan Reservoir, and Skeleton Reservoir were identified in the OCWP Reservoir Viability Study report as nearby viable reservoir sites. The Hydro Reservoir site is approximately 20 miles from the center of Basin 51. Hennessey, Navina, Sheridan, and Skeleton Reservoir sites are approximately 35-45 miles from the center of Basin 51. However, a detailed evaluation of the feasibility of any reservoir would be needed and should include consideration of existing land ownership, costs, geology, water quality, and permitting/ compact obligations. Section 4
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Marginal Water Quality Water Use
The OCWP MQW Work Group Final Report identified areas where there is potential for use of MQW to offset a significant amount of future demand. Basin 51 was found to have significant brackish marginal quality groundwater sources that could be used to meet a portion of the Basin’s M&I and Livestock demand. These groundwater sources are typically deeper than fresh water aquifers and not associated with delineated aquifers. The use of these supplies for M&I demand may require advanced treatment processes, such as reverse osmosis (RO) or ion exchange. OWRB does not have regulatory authority to permit withdrawals of groundwater with TDS concentrations greater than 5,000 mg/L. The USGS is currently conducting a 3-year study (to be completed in 2012) to delineate and assess saline groundwater supplies (including brackish groundwater) in Oklahoma and surrounding states. Brackish groundwater underlies the entire basin and should be evaluated as a potential short– to long-term water supply option. However, these supplies will likely be less preferable than supplies from the lower-salinity North Canadian River aquifer.
Summary of Supply Options
Short-term to long-term water supply options for Basin 51 include reducing M&I demand through moderately expanded conservation measures, increasing Crop Irrigation efficiency, continued use of the North Canadian River and Canadian River aquifers, and expanded regional partnerships with metro area communities. Long-term water supply options may include substantially expanded conservation in the M&I and Crop Irrigation demand sectors, out-of-basin supplies from a new reservoir, wholesale water purchases from regional water providers, or brackish groundwater supplies. However, due to the scale and complexity of these long-term supplies, the cost-effectiveness of these supplies needs to be evaluated against other options on a local level.
4.1.3.9 Summary of Solutions for Basin 54 (Upper North Canadian River-3)
Basin 54 (Upper North Canadian River-3) is a bedrock groundwater hot spot, where storage depletions are expected to present water supply challenges based on the overall size of the depletions and for the rate of those depletions relative to the amount of groundwater storage in the Ogallala aquifer. Shortages in the basin are in large part driven by the significant seasonal demand of the area's Crop Irrigation practices. More detailed information on this basin is available in the OCWP Water Supply Hot Spot Identification and Analysis report and the Panhandle Watershed Region Planning Report. In addition to bedrock groundwater storage depletions, alluvial groundwater storage depletions may occur in Basin 54 by 2020 and surface water gaps may occur by 2030. Six categories of supply options for mitigating groundwater storage depletions in Basin 54 are summarized in Table 4-11 and described in the text below. Section 4
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Table 4-11 Summary of Water Supply Options for Basin 54 Water Supply Option Option Feasibility
Demand Reduction
 Increased Crop Irrigation efficiency
 Shift to crops with lower water demand
 Short- to long-term solution that could reduce 2060 groundwater depletions by 15% to 99% and surface water gaps by about 35%.
Increased Reliance on Surface Water
 Increased use of surface water supplies, without reservoir storage
 Not feasible
Increased Reliance on Groundwater
 Increased reliance on the Ogallala aquifer
 Short-term solution; not sustainable and may not be cost-effective in the long term
Marginal Quality Water Use
 Use of marginal water quality sources
 No significant sources identified; site-specific potential for reuse of oil and gas flowback and produced water for oil and gas drilling and operations
Reservoir Storage
 Development of new reservoirs
 Not feasible
Out-of-Basin Supplies
 Englewood Reservoir or Statewide Water Conveyance
 Potential long-term solution
Demand Reduction
Demand reduction could reduce surface water gaps or groundwater storage depletions through expanded permanent conservation measures. Increasing the sprinkler irrigation efficiency in the Crop Irrigation demand (Scenario I conservation, as defined in the OCWP Water Demand Forecast Report) could reduce the demand by 1,400 AFY and reduce the size of the annual groundwater storage depletions in 2060 by about 15 percent, to a value of 7,720 AFY. This conservation measure could benefit users throughout the basin and should be considered as a short– to long-term water supply option.
Current crops are predominantly forage crops, and to a lesser extent, wheat and other crops. A shift from crops with high water demand (e.g., corn for grain and forage crops) to low water demand crops such as sorghum for grain or wheat for grain (Scenario II conservation) could reduce demand by 10,170 AFY and reduce the size of the annual groundwater storage depletions by about 99 percent, to a value of 70 AFY. This measure could benefit users throughout the basin and should be considered as a long-term water supply option. Additional conservation measures in the M&I demand sector may help reduce the adverse effects of localized storage depletions, but will not have a significant impact basin wide because the basin's M&I demand is significantly less than that of the Crop Irrigation demand sector.
Increased Reliance on Surface Water Supplies
Surface water in the basin is fully allocated, limiting diversions to existing permitted amounts. There is a moderate to high probability of surface water gaps starting in 2040 for the baseline demand projections. Increased reliance on surface water use, if permits could be issued, would increase the size and probability of these gaps. Therefore, increased reliance on Basin 54 surface water supplies is not recommended.
Increased Reliance on Groundwater Supplies
The primary source of water (95 percent of the total demand) in this basin is bedrock groundwater from the Ogallala aquifer. Water levels in Basin 54's portion of the Ogallala Section 4
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aquifer have remained relatively constant or have been increasing in recent years (OWRB Mass Well Measurement 2011). Under baseline demand, storage depletions are expected to increase due largely to the growth in Crop Irrigation demand. These storage depletions may cause declining water levels that could result in higher pumping costs, the need for deeper wells, and potentially changes to well yields or water quality. The projected growth in surface water and alluvial groundwater use could instead be supplied by the Ogallala aquifer, which would result in small (550 AFY) increases in projected storage depletions. Additionally, some M&I water users could consider obtaining wholesale water supplies from water providers with wells in more dependable portions of the Ogallala aquifer. The development of additional bedrock groundwater supplies should be considered a short-term water supply option. Over the long term, the increased depletions of stored water would likely lead to decreased well yields and increased pumping costs, making demand reduction and other supply options more sustainable and cost-effective.
Use of alluvial groundwater instead of increasing surface water use would increase alluvial groundwater storage depletions by 100 AFY by 2060. However, the majority of alluvial groundwater use is from non-delineated minor aquifers on Wolf Creek. Therefore, increased reliance on these supplies is not recommended without site-specific information.
Reservoir Storage
The OCWP Reservoir Viability Study evaluated the potential for reservoirs throughout the state; no viable sites were identified in Basin 54. Also, the surface water in Basin 54 has been fully allocated for permits. Therefore, development of additional reservoir storage in Basin 54 is not recommended.
Out-of-Basin Supplies
Out-of-basin supplies would be among the most costly of options, but could eliminate the potential for surface water gaps and groundwater depletions. The development of out-of-basin supplies should be considered as a long-term water supply option for users throughout the basin. However, due to the scale and complexity of developing out-of-basin supplies, the cost-effectiveness of these supplies needs to be evaluated against other options on a local level. Potential out-of-basin supplies include Englewood Reservoir and the statewide conveyance system. Englewood Reservoir was identified in the OCWP Reservoir Viability Study report as the nearest viable reservoir site to the basin, although it would be 90 miles or more away from the majority of users in Basin 54. This reservoir also would require approval of the Kansas-Oklahoma Arkansas River Compact Commission. With new terminal storage of about 5,000 AF, a 30-inch diameter pipe would be needed to bring out-of-basin supplies at a constant flow rate into Basin 54 for further distribution to users. With no terminal storage and variable flows in the pipeline, a 54-inch diameter pipeline would be needed.
Three alternatives for the statewide water conveyance system to deliver water to the Panhandle Region were identified in the OWRB Water Conveyance Alternatives report. All of the alternatives require additional reservoirs, hundreds of miles of piping, canals, and Section 4
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inverted siphons, and many pumping plants. Due to the scale and complexity of developing out-of-basin supplies, the cost-effectiveness of these supplies should be evaluated against other options on a local level. The development of out-of-basin supplies should be considered as a long-term water supply option for users throughout the Basin.
Marginal Water Quality Water Use
The OCWP MQW Work Group Final Report identified areas where there is potential for use of MQW to offset a significant amount of future demand. However, Basin 54 was not found to have significant marginal quality sources or significant potential to offset demand with MQW. The Oil and Gas demand sector could potentially use marginal quality water from oil and gas flowback or produced water for drilling and operational activities. Opportunities to reuse flowback or produced water should be considered on an individual well field basis for cost-effectiveness relative to other available supplies.
Summary of Supply Options
Short-term water supply options for Basin 54 include increasing crop irrigation efficiency and increased use of the Ogallala bedrock aquifer. Long-term water supply options may include a shift to crops with a lower water demand, out-of-basin supplies from Englewood Reservoir, or the statewide water conveyance system. However, due to the scale and complexity of these long-term supplies, the cost-effectiveness of these supplies should be evaluated against other options on a local level.
4.1.3.10 Summary of Solutions for Basin 55 (North Canadian Headwaters) and Basin 66 (Cimarron Headwaters)
Basin 55 (North Canadian Headwaters) and Basin 66 (Cimarron Headwaters) are adjacent basins with very similar water supply needs and resources; therefore, they were evaluated as a single hot spot. Basins 55 and 66 are bedrock groundwater hot spots and Basin 66 is a surface water hot spot. Storage depletions in both basins are expected to present water supply challenges based on the overall size of the depletions and for the rate of those depletions relative to the amount of groundwater storage in the Ogallala aquifer. Surface water issues in Basin 66 are mainly due to the basin's low physical availability of streamflow and lack of available streamflow for new permits. Shortages in the basins are in large part driven by the significant seasonal demand of the area's Crop Irrigation practices. More detailed information on these basins is available in the OCWP Water Supply Hot Spot Identification and Analysis report. In addition to challenges noted above, surface water gaps and alluvial groundwater storage depletions may occur in Basin 55 by 2020 and alluvial groundwater storage depletions may occur in Basin 66 by 2050. Six categories of supply options for mitigating surface the projected surface water gaps and groundwater storage depletions in Basins 55 and 56 are summarized in Table 4-12 and described in the text below. Section 4
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Table 4-12 Summary of Water Supply Options for Basins 55 and 66 Water Supply Option Option Feasibility
Demand Reduction
 Increased irrigation efficiency
 Shift to crops with lower water demand
 Short- to long-term solution that may reduce groundwater storage depletions by 30% to about 90% and surface water gaps by up to 75%.
Increased Reliance on Surface Water
 Increased use of surface water supplies, without reservoir storage
 Not feasible
Increased Reliance on Groundwater
 Increased reliance on the Ogallala aquifer instead of increased surface water and alluvial groundwater use
 Short-term solution; not sustainable and may not be cost-effective in the long term
Marginal Quality Water Use
 Use of marginal water quality sources
 No significant sources identified
Reservoir Storage
 Development of new reservoirs
 Not feasible
Out-of-Basin Supplies
 Englewood Reservoir and Statewide Water Conveyance
 Potential long-term solution
Demand Reduction
Demand reduction could reduce surface water gaps or groundwater storage depletions through expanded permanent conservation measures. Increasing the sprinkler irrigation efficiency in the Crop Irrigation demand (Scenario I conservation, as defined in the OCWP Water Demand Forecast Report) could reduce the demand by 14,340 AFY and reduce the size of the annual bedrock groundwater storage depletions in 2060 by about 30 percent, to a value of 37,110 AFY. This conservation measure could benefit users throughout the basins and should be considered as a short– to long-term water supply option.
Currently crops are predominantly wheat and corn and to a lesser extent forage crops. A shift from crops with high water demand (e.g., corn for grain and forage crops) to low water demand crops such as sorghum for grain or wheat for grain (Scenario II conservation) could reduce demand by 65,526 AFY and reduce the size of the annual groundwater storage depletions by about 90 percent, to a value of 6,650 AFY. This measure could benefit users throughout the basins and should be considered as a long-term water supply option. Additional conservation measures in the M&I demand sector may help reduce the adverse effects of localized storage depletions, but will not have a significant impact basin wide because the basins' M&I demand is significantly less than that of the Crop Irrigation demand sector.
Increased Reliance on Surface Water Supplies
Surface water in the basin is fully allocated, limiting diversions to existing permitted amounts. There is a moderate to high probability of surface water gaps in both basins starting in 2020 for the baseline demand projections. Increased reliance on surface water use, if permits could be issued, would increase these gaps. Therefore, increased reliance on Basin 55 and 66 surface water supplies is not recommended.
Increased Reliance on Groundwater Supplies
The primary source of water (98 percent of the total demand) in these basins is bedrock groundwater from the Ogallala aquifer. Water levels in Ogallala aquifer have declined Section 4
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substantially in many areas (OWRB 2006); however, the rate of water level declines has slowed due to the efforts of the Panhandle community (OWRB Mass Well Measurement 2011). Under baseline demand, storage depletions are expected to increase due largely to the growth in Crop Irrigation in the basins. These declining water levels could result in higher pumping costs, the need for deeper wells, and potentially changes to well yields or water quality. The projected growth in surface water and alluvial groundwater use could instead be supplied by the Ogallala aquifer, which would result in minimal (800 AFY) increases in projected storage depletions. Additionally, some M&I water users could consider obtaining wholesale water supplies from water providers with wells in more dependable portions of the Ogallala aquifer. The development of groundwater supplies should be considered a short-term water supply option. Over time, the Ogallala may no longer be the most cost-effective source of supply in the basins as water levels decrease. Therefore, additional long-term water supplies should be considered.
Use of additional alluvial groundwater instead of increasing surface water use would increase alluvial groundwater storage depletions by 190 AFY by 2060. However, the majority of alluvial groundwater use is from non-delineated minor aquifers. Therefore, increased reliance on these supplies is not recommended without site-specific information.
Reservoir Storage
The development of reservoir storage in Basins 55 and 66 is not recommended. The OCWP Reservoir Viability Study report evaluated the potential for reservoirs throughout the state; no viable sites were identified in Basins 55 and 66. Additionally, basin-level evaluations in the Regional Report indicate that the streamflow in these basins could supply little dependable yield, which is consistent with the conditions seen in Lake Optima.
Out-of-Basin Supplies
Out-of-basin supplies would be expected to be among the most costly of options, but would be able to eliminate the potential for surface water gaps and groundwater depletions. The development of out-of-basin supplies should be considered as a long-term water supply option for users throughout the basins. However, due to the scale and complexity of developing out-of-basin supplies, the cost-effectiveness of these supplies needs to be evaluated against other options on a local level. Potential out-of-basin supplies include Englewood Reservoir and the statewide conveyance system. Englewood Reservoir was identified in the OCWP Reservoir Viability Study report as the nearest viable reservoir site to the basins, although it would be 90 miles or more away from the majority of users in Basins 55 and 56. This reservoir also would require approval of the Kansas-Oklahoma-Arkansas River Compact Commission. With new terminal storage of about 16,000 AF, a 54-inch diameter pipe would be needed to bring out-of-basin supplies into Basins 55 and 56 for further distribution to users and eliminate gaps and storage depletions. With no terminal storage, an 84-inch diameter pipeline would be needed.
Three alternatives for the statewide water conveyance system to deliver water to the Panhandle Region were identified in the OWRB Water Conveyance Alternatives report. All Section 4
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of the alternatives require additional reservoirs, hundreds of miles of piping, canals, and inverted siphons, and many pumping plants.
Marginal Water Quality Water Use
The OCWP Senate Bill 1627 MQW Work Group Final Report identified areas where there is potential for use of marginal quality water to meet future demand. However, Basins 55 and 56 were not found to have significant marginal quality sources or significant potential to offset demand with MQW. The Oil and Gas demand sector could potentially use MQW for drilling and operational activities, but the use of this MQW source could not be estimated, since any use would be on a well by well basis.
Summary of Supply Options
Short-term water supply options for Basins 55 and 56 include increasing irrigation efficiency and increased use of the Ogallala aquifer. Long-term water supply options may include a shift to crops with a lower water demand, out-of-basin supplies from Englewood Reservoir, or the statewide water conveyance system. However, due to the scale and complexity of these long-term supplies, the cost-effectiveness of these supplies needs to be evaluated against other options on a local level.
4.2 Aquifer Recharge
The Oklahoma Legislature passed Senate Bill 1410 (SB1410) in 2008, requiring OWRB to develop and implement criteria to prioritize potential locations throughout Oklahoma where AR demonstration projects may be most feasible.
The goal of the Phase 1 investigation, conducted as part of the current OCWP update with significant work group participation from numerous water agencies and user groups, was to identify locations in both alluvial and bedrock aquifer settings that would be most suitable for AR demonstration projects to help meet future water supply challenges. A future Phase 2 would implement the recommendations from Phase 1, including pilot project field demonstration(s) of AR. Phase 1 investigations primarily sought opportunities to implement a demonstration project in conjunction with a public water supplier, but other users could also benefit from a demonstration-scale or full-scale recharge project.
The OWRB has successfully demonstrated AR in the Blaine aquifer in southwest Oklahoma. The sites were in karst aquifers and utilized gravity flow infiltration and recharge methods. Sites in this area were not considered in this study since AR has already been demonstrated in that region.
4.2.1 Site Screening Process
Criteria were developed for both a preliminary screening and a more detailed ranking process. The purpose of the preliminary screening was to eliminate many areas from further consideration based on relatively simple application of a small number of the criteria. All sites not eliminated through the preliminary screening would likely be suitable for an AR demonstration project. The more detailed ranking process identified the most feasible of the suitable sites identified through the preliminary screening. Section 4
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The preliminary screening was divided into a fatal flaw analysis and a threshold analysis. The fatal flaw analysis applies a limited set of criteria that, if the necessary characteristics are not present, would eliminate regions or aquifers from any further analysis. The fatal flaw screening criteria were developed to be able to use readily available information and relatively simple analyses of data. The threshold level screening was used to eliminate additional aquifers or areas from further consideration based on several key factors, and thus will expedite the more detailed analysis of remaining areas.
Based on discussions at the OWRB work groups, previous regional studies and national guidelines and standards set forth by government and professional organizations, the following criteria categories were used in the evaluation of potential AR locations.
 Demand
 Source Water
 Hydrogeologic Suitability
 Groundwater Quality
 Cost
 Project Impact
The boundaries of a preliminary screening site are not set and in some instances were expanded or moved in the detailed analysis. The maps presented in the detailed analysis appendices use the term recharge region, referring to the preliminary screening township-sized site. Within each recharge region, there is at least one recharge area of approximately 1 square mile and can be referred to as a site in the detailed analysis. Smaller design-level sites were not identified as part of this phase of the pilot project and are anticipated for Phase 2.
Several sites were screened out through a fatal flaw analysis, resulting in 15 alluvial aquifer sites and 15 bedrock sites. A threshold analysis screened out an additional 15 sites, resulting in 6 alluvial sites and 9 bedrock sites. The 15 sites that passed the fatal flaw and threshold screening (Figure 4-2) were considered in a detailed ranking process. Section 4
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Figure 4-2 – Location of Sites that Passed Fatal Flaw and Threshold Screening
4.2.2 Recommended Sites for Recharge Pilot Project
At the April 2010 work group meeting, three short-listed sites (site 12, Ada; site 42, Eakly; site 19, Woodward) were discussed in detail. The work group expanded the recommended number of sites to include two alternates in case local interest is low or new information from follow-up investigations at the recommended sites reveals a limiting factor. The work group selected site numbers 15 (Durant) and 30 (Enid). These sites were added as alternatives because they were consistently in the top group of sites in the rankings under various criteria weightings tested at the work group meeting, and one is a bedrock aquifer (Site 15, Durant, Antlers aquifer) and the other is an alluvial aquifer that can utilize a lower-cost spreading basin (Site 30, Enid, Isolated Terrace Aquifer). The selected sites are described below.
Recharge Region 12 (near Ada)
Recharge region 12 is located near the Town of Ada, with the Blue River providing a water source and the Arbuckle Simpson aquifer providing storage. The Blue River appears to provide adequate source, although the nearest gage is located approximately 17 miles downstream of the probable diversion location for a project. There are no upstream gages to help better quantify source availability, but based on basin size, the source location appears to have an adequate supply. The Town of Ada has existing wells in the vicinity of the recharge region, making it a good candidate for a recharge project. Additionally, there Section 4
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is plentiful storage, and the residence time is appropriate for a pilot project. Given the channelized nature of the karst aquifer, specific site investigations would be required to ensure the recharged water could be recovered. The Blue River had minimal maximum contaminant level (MCL) exceedences, and low TDS concentrations, suggesting that pretreatment would not be required. Also, the Langelier indices for the Blue River and Arbuckle Simpson aquifer provided one of the closest pairings of all recharge regions. Perhaps the most negative aspect of Recharge Region 12 is the requirement of a pipeline to convey water from the source to the project site. However, the majority of recharge regions included this requirement, and most would require a longer pipeline than Recharge Site 12.
Recharge Region 42 (near Eakly)
Recharge region 42 is located near the Town of Eakly, with Lake Creek providing a water source and the Rush Springs aquifer providing storage. Demand for the entire town is approximately 250 AFY, so a pilot project could potentially meet the entire demand for the town. Flows in Lake Creek are subject to regulation due to nearby Fort Cobb Reservoir, which may limit the supply availability; however the relatively small amount of water required for the project may be negligible compared to the reservoir yield requirements. Overall, Lake Creek appears to provide adequate source, even during drought years. The Town of Eakly has two existing PWS wells in the vicinity of the recharge region, making it a good candidate for a recharge project. Additionally, there is plentiful storage, and the residence time is appropriate for a pilot project. There was limited water quality data available from Lake Creek, but nearby Cobb Creek exceeded MCLs infrequently. Only one sample was collected from Cobb Creek for TDS, and it slightly exceeded the MCL. Thus, it is strongly recommended that further water quality characterization be completed prior to implementing a pilot project at this recharge region to help determine the need for pre-treatment. The Oklahoma Corporation Commission (OCC) provided oil and gas well locations in the area. The nearest wells were over a mile from the recharge region and so were not considered to be detrimental to the site. Recharge Region 42 would also require a pipeline to convey water from the source to the project, and the pipeline is longer than that of Recharge Region 12.
Recharge Region 19 (near Woodward)
Recharge region 19 is located near the Town of Woodward, with the North Canadian River providing a water source, and the North Canadian alluvial terrace aquifer providing storage. The hydrogeologic characteristics of this site are very favorable for a recharge project, and this region is the only alluvial site of the three recommended sites, allowing for use of spreading basins instead of injection wells. Woodward provides an appropriate level of demand for a pilot project. In a representative low-precipitation year, there was approximately 90,000 AF at a downstream gage. Supply for a pilot project scale (maximum of 1,000 AF) is most likely available, but could be tempered by Canton Reservoir's yield requirement. Native groundwater quality is good, but source water quality has exceeded MCL for several parameters in the past. Section 4
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The work group suggested that the high TDS levels in the source water were isolated events from nearby oil and gas operations and water source quality may be better than the annual analysis indicated, especially during the high flow times of year when a recharge project would be operating. TDS measurements were examined on a monthly basis, and showed that TDS decreases in the higher flow months, but still exceeds the MCL in those months. Almost none of the TDS measurements for the site were below the MCL. The source water quality data thus indicate pre-treatment would be required before recharging the aquifer. A pipeline approximately 2 miles long would be required to bring water from the North Canadian River to the recharge location.
Alternate Recharge Region 15 (near Durant)
Recharge region 15 is located near the Town of Durant, with the Blue River providing a water source and the Antlers aquifer providing storage. The Blue River appears to provide adequate source, although the nearest gage is located approximately 8 miles downstream of the probable diversion location for a project. There are several tributary streams that enter the Blue River between the probable point of diversion and the downstream gage, but the majority of the basin lies upstream of that point, suggesting that flows associated with those tributaries likely do not have a large impact on the river. The representative low-precipitation year had flows greater than 120,000 AF, suggesting there is plentiful water for a project. Water quality data for both source and groundwater are generally good, although the geochemistry was unable to be effectively compared due to a lack of hardness data. One of the largest hindrances to a project is the proposed location and lack of infrastructure. There are no existing high-capacity wells in the vicinity of the proposed location, and the area is approximately 2 miles from both the Blue River and Durant. Thus, this location will require installation of aquifer storage and recovery (ASR) wells and construction of transfer pipelines.
Alternate Recharge Region 30 (near Enid)
Recharge region 30 is located near the Town of Enid, with Skeleton Creek providing a water source, and the Enid isolated terrace aquifer providing storage. The hydrogeologic characteristics of this site are very favorable for a recharge project, with injection wells nearby or the potential to use spreading basins instead of injection wells. The nearest gage is 7 miles downstream, and annual flow during the representative low-flow year was only approximately 16,000 AF. There may be issues with supplying the project during low-flow seasons. No surface water data was available for Skeleton Creek, suggesting that a monitoring program should be implemented prior to selection of the area for a project. Groundwater quality was relatively good, with few MCL exce