Aquifer Storage & Recovery (ASR) and Reuse

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1 Aquifer Storage & Recovery (ASR) and Reuse The Perfect Match for Water Resource Managers October 17,

2 Outline Oklahoma Drought Tolerance What is ASR and How Does it Work? Latest Legislation and Regulations Supply Diversification with ASR Benefits & Challenges 2

3 3 Oklahoma Drought Tolerance

4 Historically surface water has been so reliable Oklahoma 55,646 miles of shoreline Surface water reservoirs developed in early 1900s Cheap and effective way to quickly store large volumes of water o 4,773 reservoirs in OK o 13 million ac-ft of water Surface water reservoirs developed in early 1900 s Cheap and effective way to quickly store large volumes of water 4

5 Series of prolonged droughts from Drought 5

6 Droughts identified vulnerability associated with relying on one source type for supply Lake Draper - 27% full September 2011 Lake Hefner 35% and Lake Atoka 51% full 2013 KGOU 6

7 Aquifer Storage and Recovery (ASR) can be incorporated into the water management tools Increase available water supply Reduce dependence on aquifers for new supply 23 aquifers store estimated 320 million ac-ft Only ½ of OK groundwater is recoverable Reuse treated wastewater Limit evaporation from supply water Maximize existing infrastructure or water rights Conservation management Further reduce diversions during drought Store excess water during floods 7

8 8 What is ASR and How Does it Work?

9 ASR is injection of surplus water into an aquifer for subsequent recovery to meet future demands Raw Water Withdrawal Raw Water Storage Water Treatment Plant or Advanced Water Treatment ASR Well Treated Water Storage 9

10 Source water is pumped into the aquifer to store and pumped out for use 10

11 ASR is similar to surface storage Characteristic ASR Surface Reservoir Pump source into storage Helps meet drought, seasonal, & diurnal demands Treat surface water before storage Unlikely Treat groundwater before storage Maybe Unlikely Pump source out of storage for use Maybe Treat stored water after release/recovery Maybe Evaporation & sedimentation losses No ASR is a management tool for engineered storage but does not create water 11

12 12 Latest Legislation & Regulation in Oklahoma

13 ASR is widely used throughout the U.S. CH2M Projects Operational ASR Piloting & Demonstration Feasibility & Initial Investigation

14 Timeline of ASR & Reuse in Oklahoma Proposed 2016 revision to GW quality standards (for adoption in 2017) Antidegradation policy (785:45-7-2) Beneficial uses domestic untreated water supply & public water supply for explicit independent protection (785:45-7-3) Oklahoma Comprehensive Water Plan (2012) Regulates quality and quantity Water for 2060 Consume no more fresh water in year 2060 while continuing to grow the population and economy ASR Workgroup formed SB 1184 (2014) Allows ODEQ to consider pointsource reuse discharge Advisory council recommends promoting use of marginal waters Criteria broad quality protection; specific numeric criteria for several constituents (785:45-7-4) SB 1219 (2016) Water rights legislation gives OWRB ability to promulgate ASR rules Final rules in progress ODEQ working on rules for injection, infiltration basins, and the construction of treatment facilities Final Reuse rule adoption in fall

15 15 Supply Diversification with ASR

16 Annual Volume (ac-ft) Surface water supplies dwindle during drought 25,000 20,000 Severe Drought WTP capacity 15,000 Demand 10,000 Drought supply 5, Available Surface Water Supply WTP Capacity Target Drought Supply Year Available Surface Water for ASR Storage Average Unrestricted Demand

17 Annual Volume (ac-ft) ASR storage helps meet drought demands 25,000 Severe Drought 20,000 15,000 10,000 5, Production from ASR Available Surface Water Supply Average Unrestricted Demand Year Available Surface Water for ASR Storage WTP Capacity Target Drought Supply

18 Annual Volume (ac-ft) Cumulative ASR Storage (ac-ft) ASR storage decreases and then recovers 25,000 Severe Drought 45,000 40,000 20,000 35,000 30,000 15,000 25,000 10,000 20,000 15,000 5,000 10,000 5, Available Surface Water Supply ASR Production Average Unrestricted Demand Year Available Surface Water for Storage WTP Capacity Target Drought Supply

19 19 Drought is a recent driver for direct potable reuse projects

20 Annual Volume (ac-ft) Direct potable reuse is used during drought 30,000 Severe Drought 25,000 20,000 WTP capacity 15,000 Demand 10,000 Drought supply 5, Year Suface Water DRP

21 But there s challenges to DPR Public acceptance challenges High capital and O&M cost Useful during intermittent operation (drought only) 21

22 ASR enhances IPR for drought supply Indirect Direct potable reuse using ASR Public acceptance challenges High capital and O&M cost Useful during intermittent operation (drought only) peaking and seasonal uses Potential to replace treatment processes reduced ASR 22

23 Annual Volume (Acre-ft) Reduce direct potable reuse plant size and store excess reuse 30,000 Severe Drought 25,000 20,000 WTP capacity 15,000 Demand 10,000 5,000 Drought supply Year Suface Water DPR IPR Storage

24 Annual Volume (acre-ft) Recover reuse from ASR to meet supply 30,000 Severe Drought 25,000 20,000 WTP capacity 15,000 Demand 10,000 Drought supply 5, Year Suface Water DPR IPR Recovery

25 25 Benefits & Challenges

26 Strategy Benefits Challenges Surface Water & ASR Direct Potable Reuse Quicker to implement Low cost Maximize available treatment facilities and infrastructure Less SW reliance Maximize available WTP facilities DPR & ASR Less SW reliance Increased public acceptance Maximize available WTP facilities Susceptible during extended droughts Competing users for source water Requires time to fill storage Requires pilot testing and suitable geology Public acceptance High cost Intermittent use Moderate cost Requires time to fill storage Requires pilot testing and suitable geology 26

27 ASR feasibility is dependent on many factors Aquifer suitability Source water Quality Availability Infrastructure: ASR facilities Conveyance infrastructure from ASR to source Adaptability of existing infrastructure Additional treatment facilities Costs of recoverable water compared to alternative supplies Quality/compatibility of storage zone 27

28 Questions? Lindsay Atkinson, PE (720) Andrea DuMont, PE (512)