Transcript Slide 1
Impoundments: Research-based Alternative Management Concepts Ed Hanlon, Soil & Water Concepts Sanjay Shukla, Hydrology and Water Quality Concepts Marty Main, Wildlife Research Pam Roberts, Plant Pathology Research Tatiana Borisova, Water Economics and Policy Managing the Land to Manage the Water 1 Impoundments in Caloosahatchee Basin Lake Okeechobee Permitted (1 inch) Distributed Privately owned ~1/3 have functional wetlands ~2/3 have additional uplands All of them leak! Clewiston LaBelle Ft. Myers Water Use Permits Impoundments N W E S 0 20 Miles 2 Upland Impoundment 3500 31 Impoundment - returnflow Impoundment - outf low Impoundment - w es t side 3000 rain dis charge C-pump 2500 Water level (ft NGVD) 29 2000 ground 28 1500 27 1000 26 500 0 25 O-99 Pump (rpm) or Rain (in x 1000) 30 N-99 D-99 J-00 F-00 M-00 A-00 M-00 J-00 J-00 A-00 S-00 O-00 N-00 D-00 J-01 3 Water Budget for Impoundments Evapotranspiration (4 to 32%) Rain (4 to 29%) Pumped inflow 71 to 96% Outflow 31 – 39% subsurface movement 35 to 61% 4 Water Supply from Impoundments Alternative Thickness (in) Description 6 Lining entire reservoir 1 2 3 6 12 N/A Lining inside ditch and embankments Lining inside ditch and embankments Recirculation Weeks of irrigation 13 3 4 4 Weeks of irrigation based on average weekly use in the grove during the irrigation season Shukla and Jaber (2006, 2005, 2004) – EDIS, ASCE Hydrol. Engg, ASCE Irrig. and Drain. Engg, and ASAE Transact. 5 Wildlife in Impoundments • Most avian species/numbers: Wetlands • Seasonal water levels influenced bird community changes • Bird species/numbers increased with lower water levels (foraging habitat improved) • Deer, hogs (panther prey): Uplands 6 • 85 avian species, resident and migratory • 37% of native avian species • 65% of nesting birds • 5 species, state or federally listed 7 Impoundments Permitted Impoundments Retain Stormwater (1 inch=2 feet depth) Provide Habitat Improve Water Quality Additional Strategies Increase retention (store more than 1 inch) Control water level in wetlands and ephemeral zone (berms, for example) Re-use water at beginning of dry season 8 Options for Using Water from Impoundment Agricultural (and urban) irrigation Reduce groundwater usage Urban/Agricultural partnership Water quality / quantity credit trading Distributed impoundments – water supply – ASR Encourage landowners to store water (internal drainage or external) ASR: Aquifer Storage and Recovery 9 Impoundments Recyclable Water Containment Area (RWCA) • Land temporarily used to contain water for water quality and storage purposes • Land is later returned to other uses (rotation) RWCAs: Recycle nutrients; Store water; Release water slowly; Decrease flows to the coast 10 RWCA • 40% of water movement is through berm to Outside Borrow Ditch • Co-precipitation of P and organics is possible (Hanlon et al., 2007) • Treatment byproducts may be returned to crop land safely • Proof of concept stage 11 Tailwater Recovery Systems • Collects water on downhill side from agricultural operations • Pumping moves water for irrigation reuse • Decreased Consumptive Use • Must address risk of disease for crops 12 Disease Risks Percentage of Pythium species causing pre- and post-emergence damping off 13% 9% 13% 35% Pythium Group F P. aphanidermatum P. myriotylum Pythium spp. P. irregulare 30% 13 Disease Risks • Slow Sand Filtration – Prevents spread of pathogens – Effectively removes human and animal contaminants (fecal coliforms-yuck) – Colonized by suppressive microorganisms – Proven for commercial nursery and greenhouse operations • Not demonstrated for vegetables, sugarcane, and field forages 14 Re-use from Current Structures with Soil Filtration 15 Re-use from Current Structures with Soil Filtration 16 Water Quality Credit Trading Innovative mechanism proposed to address surface water quality Objectives: Reduce the overall cost of meeting water quality goals in a basin Allow individual entities flexibility in choosing pollution abatement technologies Provide individual entities with incentives to innovate in the pollution abatement sphere Address future growth in the basin while meeting water quality goals 17 How Does Water Quality Credit Trading Work? Pollution control costs can differ from source to source. Overall costs of achieving pollution reduction goals in a Basin can be minimized by allowing sources to reallocate reductions according to their pollutionabatement costs. Well-designed trading programs can achieve this allocation by harnessing the forces of the market. 18 Simplified Example Two separate entities within a basin Each have a water discharge that contributes to phosphorus (P) loading. 19 Simplified Example (cont.) Trading scenario: WWTP would pay the farmer to remove an extra unit of phosphorus at the lower cost. Payment that the WWTP makes to the farmer is negotiated between them. 20 Challenges Setting pollution cap / baseline for individual entities Measuring pollution reduction credits High transaction costs of finding trading partner and negotiating agreement Enforcing trading contract and liability issues P, N $ 21 Water Quality Credit Trading – Nationwide Perspective Source: US EPA 2008. http://www.epa.gov/owow/watershed/trading/tradingmap.html 22 Water Quality Credit Trading – Nationwide Perspective (cont.) US EPA: 2003: Final Water Quality Trading Policy. (http://www.epa.gov/owow/watershed/trading/finalpolicy2003.html ) 2004: Water Quality Trading Assessment Handbook (http://www.epa.gov/owow/watershed/trading/handbook/ ) 2007: Watershed-Based NPDES Permitting (http://cfpub.epa.gov/npdes/wqbasedpermitting/wspermitting.cfm ) USDA: 2006: Water Quality Credit Trading Agreement with US EPA (http://www.nrcs.usda.gov/news/releases/2006/usdaepawqagreement.html ) 23 Water Quality Credit Trading - Florida FDEP. 2006. Water Quality Credit Trading: A Report to the Governor and Legislature. (http://www.dep.state.fl.us/water/tmdl/docs/WQ_CreditTradingReport_final_December2006.pdf ) CS/HB 547: Water Pollution Control (http://www.myfloridahouse.gov/sections/bills/billsdetail.aspx?BillId=37955 ) Lower St. Johns River TMDL Executive Committee. 2008. Lower St Johns River Basin Management Action Plan (Draft) (http://www.dep.state.fl.us/northeast/stjohns/TMDL/tmdl_announcements.htm ) 24 Potential Water Quantity Credits If allowed by regulations: Quantity credits for reducing urban stormwater volume? Quantity credits for alternative on-farm stormwater use? Reduction of agricultural water pumping from ground / surface water sources? 25 Your turn… 26