The Feasibility of Using Reclaimed Water for Direct and Indirect Aquifer Recharge in the Tampa Bay Area

Transcription

1 The Feasibility of Using Reclaimed Water for Direct and Indirect Aquifer Recharge in the Tampa Bay Area Sandie Will, P.G. Hydrologic Evaluation Section

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3 Project Area Southern Hillsborough and Western Polk Counties Potential availability of reclaimed water Critical water supply need SWUCA/MIA Project Area

4 Objectives Determine regulatory requirements and identify similar projects Quantify water level improvements to UFA and additional potential groundwater supplies Estimate costs

5 Types of Aquifer Recharge Indirect Direct Applied at land surface Specific hydrogeologic setting Less treatment Local improvement More land Routed into recharge wells More treatment Regional improvement Less land Salinity barrier

6 Types of Aquifer Recharge Indirect Direct Applied at land surface Specific hydrogeologic setting Less treatment Local improvement More land Routed into recharge wells More treatment Regional improvement Less land Salinity barrier

7 Types of Aquifer Recharge Indirect Direct Applied at land surface Specific hydrogeologic setting Less treatment Local improvement More land Routed into recharge wells More treatment Regional improvement Less land Salinity barrier

8 Types of Aquifer Recharge Indirect Direct Applied at land surface Specific hydrogeologic setting Less treatment Local improvement More land Routed into recharge wells More treatment Regional improvement Less land Salinity barrier

9 Water Treatment Requirements Indirect Aquifer Recharge Rapid Infiltration Basins (RIBs) Secondary treatment and basic disinfection Water Conserv II, Orlando, FL Additional treatment depends on connection to UFA

10 Water Treatment Requirements Direct Aquifer Recharge Recharge Wells Meet drinking water standards Additional treatment depends on aquifer water quality Groundwater Replenishment System, Orange County, CA

11 Upper Floridan Aquifer Water Quality Very Good (Potable) Poor Good

12 Direct Aquifer Recharge Water Treatment Requirements Poor Aquifer Water Quality Secondary Treatment Filtration Very Good (Potable) High Level Disinfection Meet Drinking Water Standards

13 Direct Aquifer Recharge Water Treatment Requirements Moderate Aquifer Water Quality Multiple barriers Total organic carbon (TOC)/Total Very Good (Potable) organic halogen (TOX) testing One-year pilot study

14 Direct Aquifer Recharge Water Treatment Requirements Potable Aquifer Water Quality Multiple barriers Carbon adsorption Very Good (Potable) Mutagenicity, TOC and TOX testing Two-year, full-scale study

15 Example Reclaimed Water Treatment Groundwater Replenishment System, Orange County, CA Microfiltration (MF) Reverse Osmosis (RO) Ultraviolet Light (UV) with Hydrogen Peroxide Recharge Well

16 Indirect Aquifer Recharge Concepts Areas Moderate connection to UFA High connection to UFA Minimal connection to UFA

17 Upper Floridan Aquifer Water Level Change Lake Wales Ridge Withdrawal -2 Withdrawal Only 4 MGD Max Drawdown = 4 ft

18 Upper Floridan Aquifer Water Level Change Lake Wales Ridge Indirect Recharge and Withdrawal Scenario Withdrawal 4 MGD Recharge 5 MGD Max Drawdown = 1 ft

19 Upper Floridan Aquifer Water Level Change Withdrawal Only - 15 MGD MIA ft PR ft 10 MGD 5 MGD

20 Upper Floridan Aquifer Water Level Change Coastal Direct Aquifer Recharge Scenario Recharge 20 MGD and Withdrawal 15 MGD 20 MGD MIA ft PR ft 10 MGD 5 MGD

21 Costs Recharge Type Capital Costs ($ Million) Production Costs ($/1,000 gal) Risk Issues Rapid Infiltration Basins (5 MGD/4 MGD) $52 $4.36 Low Land intensive Need thick surficial sands and leaky confining unit Coastal Direct Recharge (20 MGD/15 MGD) $251 $4.34 Medium Metals mobilization Inland Direct Recharge (20 MGD/15 MGD) $422 $7.84 High Metals mobilization Supplemental treatment Pilot/Full-scale testing

22 Summary of Results Recharge Type Capital Costs ($ Million) Production Costs ($/1,000 gal) Risk Issues Rapid Infiltration Basins (5 MGD/4 MGD) $52 $4.36 Low Land intensive Need thick surficial sands and leaky confining unit Coastal Direct Recharge (20 MGD/15 MGD) $251 $4.34 Medium Metals mobilization Inland Direct Recharge (20 MGD/15 MGD) $422 $7.84 High Metals mobilization Supplemental treatment Pilot/Full-scale testing

23 Next Steps Studies Site-specific Metals Mobilization Public Outreach

24 Documents and Publications Library Search: Aquifer Recharge Document Nos

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