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Louisiana Department of Environmental Quality 2010 Envirothon Training. Land Use Planning and Its Effect on Groundwater. PROBLEMS/CONCERNS. Ground-water withdrawals are lowering water levels in Louisiana aquifers.
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Louisiana Department of Environmental Quality 2010 Envirothon Training Land Use Planning and Its Effect on Groundwater
PROBLEMS/CONCERNS • Ground-water withdrawals are lowering water levels in Louisiana aquifers. • In certain areas, these withdrawals are creating conditions favorable for saltwater encroachment. • Major aquifers affected are the Sparta, Chicot, and Southern Hills aquifer systems.
Water-level decline in the Sparta aquifer in northern Louisiana during the period 1990 to 2000, based on data from USGS/DOTDwater-level networks.
Sparta Overdraft Average Usage - 70 MGD Sustainable Usage - 52 MGD Usage would have to be reduced by more than 18 MGD for the water level in the Sparta to begin to rebound.
Management of Sparta • Creation of Sparta Commission • Owners of each non-domestic well shall submit a monthly report showing the amount of water pumped on a monthly basis and the purpose for which it was used. • Aggressive education program on conservation & protection • Users of Sparta ground water shall vigorously seek alternate sources of potable water to alleviate excess usage of the Sparta Aquifer.
Alternate Sources of Water • West Monroe – Graphics Packaging • Water Re-use Project • Convert gray water into potable water • Pilot Project - 1 MGD • Ultimate Goal - 10 MGD
Water-level decline in the Chicot aquifer system during the period 1990 to 2000, based on data from the USGS/DOTD water-level network.
Management of Chicot • Sabine River Diversion Channel and Distribution System in Calcasieu Parish • Supplies water to numerous industries in the Sulphur area • Supplies water for irrigation • Lessens dependency on Chicot Aquifer • Attempts being made to establish Chicot Aquifer Stakeholders group (similar to Sparta Commission)
Hydrograph showing effect of Sabine River Diversion Canal Sabine River Diversion Canal is completed and results in less ground-water pumpage and water-level rebound
Idealized cross-section showing aquifers in the Baton Rouge area.
Management of Southern Hills Capital Area Groundwater Conservation Commission established. Reserves 1000-, 1500-, 1700-foot sands for public supply. Limits pumpagein 2000-foot sand; moratorium on wells in some areas. Connector well completed in 1999 – connects 800- and 1500-foot sands to raise water level in 1500 ft sand and inhibit movement of saltwater
Groundwater Management in Urban Areas Ordinances Site plan reviews Reuse of waste water/gray water Harvesting rainwater Drip irrigation systems Watering Schedule Public education
Groundwater Management in Rural/Agricultural Areas Irrigation management Agricultural chemical best management practices Aquifer Storage Reservoirs (ASR) Tax incentives Education/Master Farmer Program Natural Resources Conservation Service (NRCS) programs
Ground Water Basin Recharge Programs • Advantages • maintain water level in aquifer • reduce seasonal overpumping • good use for recycled water • landowner compensated for use of property • reduce subsidence caused by high pumping rates • Disadvantages • may be difficult to sustain long term • groundwater quality can be impacted • cost of maintenance • recharge area may be outside jurisdiction • cooperation from landowners