Clearwater s Groundwater Replenishment Program. Potable Reuse for Florida: A Full Day Workshop for Elected Officials Orlando, FL March 22, 2013 Nan Benne(, P.E. Public U2li2es Assistant Director City of Clearwater
Project Team Public U2lity Owner Coopera2ve Funding Partner Engineering Consultant Leggette, Brashears & Graham, Inc. Hydrogeology Consultant
Project Loca2on Gulf of Mexico Gulf of Mexico Tampa Bay Tampa Bay
Clearwater Public U2li2es Mission Statement Public Utilities is dedicated to providing highquality water, wastewater & reclaimed services while protecting the public health and natural environment of our community through cost effective management, operating and maintenance of our infrastructure sustaining these essential services.
Community Water Cycle
Integrated Water Management Strategy A holistic approach that brings together all facets of the water cycle water supply and treatment, sewage collection and treatment, purification, reuse and disposal.
Clearwater Integrated Water Management Tac2cs 1. Conserve limited water supplies 2. Preserve drinking water sources 3. Protect coastal environment 4. Produce more water locally 5. Manage the rising cost of water
City Ini2ated Reclaimed Projects
Clearwater Groundwater Replenishment Project Statement The Project proposes to construct a water purifica3on plant on the site of the City of Clearwater s exis3ng Northeast Water Reclama3on Facility for the purpose of supplying 3 MGD (million gallons per day) of highly treated water to recharge lower Zone A of the Floridan Aquifer.
Purifica2on Process Block Diagram Reclaimed Water REMOVES Suspended Solids Cryptosporidium Giardia REMOVES Bacteria Some Viruses Heavy Metals Inorganics Organics PharmaceuScals PPCP s REMOVES Viruses NDMA Low Molecular Weight Organics To Post Treatment
Water PurificaSon Process Post Purifica2on Treatment Membrane Contactors Chemical AddiSon REMOVES Dissolved Oxygen ADDS Carbon Dioxide ADDS Calcium Alkalinity Reducing Agent Ferrous Iron To Recharge Wells Arsenic Mobilization Reduce ph Adjust ph Adjust LSI Reduce ORP
Water Quality Comparison Parameter Purified Water NaSve Groundwater Total Dissolved Solids, mg/l 27 620 Calcium, mg/l 1.1 80 Magnesium, mg/l 0.2 17 Sodium, mg/l 6.5 170 Iron, mg Fe ++ /L <.01.05 Arsenic, µg/l <1.0 <1.0 Alkalinity, mg CaCO 3 /L 10.5 160 Chloride, mg/l 6.1 330 Sulfate, mg/l 0.8 16 ph 5.5 7.5 Dissolved Oxygen, mg/l >6.0 0.3 ORP, mv + -307
Conceptual Recharge System Design Water Purification Plant Proposed Recharge Well Northeast Water Reclamation Facility City Controlled Property
Recharge Well Opera2on Surficial Surficial Aquifer Supply Well Recharge Well Recharge Well Layer 1 Intermediate Confining Unit Intermediate Confining Unit Layer 2 Upper A Upper Zone A Layer 3 Floridan Aquifer Semi-Confining Unit Lower Zone Lower Zone A Layer 4 Semi-Confining Unit Semi-Confining Unit Zone B B Layer 5
Model Par2cle Tracks
Feasibility Study Proceed YES Bench, Pilot and Field Investigation Terminate Project NO Proceed? Future Field Investigation YES Full Scale Design, Permitting & Construction
Design/Permit Exploratory Well? Construct Exploratory Well Bench, Pilot and Field TesSng Phase Develop Public Outreach Strategy IdenSfy/NoSfy Stakeholders? Design/Permit Pilot Treatment System Construct Monitoring Wells/ Test Exploratory Well Construct Pilot Treatment System Operate 1 st 6 Months/Conduct Tours Collect, Analyze & Test Core Samples? Construct Recharge Treatment System Conduct 6- Month Test Operate Pilot Treatment System Last 6 Months/Conduct Tours Final Data Analysis, Modeling & Report PreparaSon? - - Project Review, Refine Tasks, Update Public Outreach Informa2on
Case for Groundwater Replenishment with Purified Water Safe, crystal clear, odorless Extends existing supplies Cost effective Extend timeframe for developing more costly supplies
Leggette, Brashears & Graham, Inc.
Ques2ons? Nan Benne\, P.E. Public USliSes Assistant Director City of Clearwater Nan.Benne\@MyClearwater.com