Aquifer Storage and Recovery in Washington. Hossein Arvan Max Golubovskiy Kirsten Wood

Transcription

1 Aquifer Storage and Recovery in Washington Hossein Arvan Max Golubovskiy Kirsten Wood

2 What is an Aquifer? underground layer of permeable rock or unconsolidated materials (gravel, sand, silt, or clay) that yields water Ponce 2007

3 Vocabulary Confined trapped between dense impermeable layers Unconfined-upper boundary is the water table Aquitard- layer that restricts flow of groundwater Aquiclude- completely impermeable aquitard Vadose zone-between land surface and saturated aquifer. Important natural defense against groundwater pollution. CARA 9, Robins 8

4 Hydraulic Characterisitcs Conductivity: m/day-ease that water moves through pore space and fractures Transmissivity: m 2 /day-measure of how fast water can move horizontally Storativity- volume of water released per unit decline in hydraulic head, per unit area of the aquifer Robins 4

5 ASR Projects Aquifer Action in WA North Bend Aquifer- up to 50 mgd (100 ft thick aquifer, 200 ft below the surface) Yakima Aquifer-annual recharge 5705 ft 3 /s (increase evapotranspiration to irrigated cropland) Lakehaven Walla Walla Redmond Spokane Aquifer Columbia Aquifer Puget Sound Aquifer System USGS 2006, Seattle Times 1994

6 ASR Purpose Capture usable excess water and detain it underground for later use Offset rising demand for drinking water Offset hydraulic variability due to climate change Prevent saltwater intrusion Prevent land subsidence Maintain baseflow in streams National Ground Water Association

7 Hydrogeologic Site Selection Criteria High Conductivity: low conductivity leads to high water levels =pressure-surface flooding, hydraulic fracturing) Low Concentrations of TDS: high TDS lowers quality water Homogeneous: heterogeneous = higher mixing and dispersion Strong aquifer materials Pyne, pg 37

8 Methods for Recharge Surface Spreading: allowing water percolate down to a shallow, unconfined aquifers Injection: pump water directly into a deep, confined aquifer Infiltration: sub-surface spreading All require periodic maintenance for clogging due to sediment settling out and microbial growth Back pg 11

9 Aquifer Storage and Recovery Pumping in excess potable water, then pumping out the same potable water that was pumped in

10 Aquifer Testing Constant pumping of water in one well while observation of aquifer drawdown in other wells Theis equation: u-dimensionless, r-recorded drawdown, t time, T-transmissivity, S-storativity Theis Function W(u) Assumes homogeneous, isotropic, confined aquifer Krešić, pg 169

11 Yakima Aquifer Needed to backup current surface water drinking supply Recharge in Winter with Naches River Flow Closed Basin with Basalt Ridges Confined Sandstone Aquifer Water level dropped 30ft in 30 years No interbasin flow Retrofitted existing well, add 2,000 gpm Pilot test 70% of recharge water recovered after 55 day storage Pumping 2,000 gpm for 30 days Appendix B, WADOE

12 Walla Walla ASR Started in 1999 Key tool in protecting Mill Creek Watershed from fire Deep Basalt Aquifers 2 wells, capable of MG/year Injected water treated with ozone and chlorine Additional wells and storage would require turbidity reduction and filtration WWW- ASR

13 Lakehaven ASR Winter recharge from Green and Cedar rivers Usable storage=29,000 acre-ft Course sands and gravels confined by aquitards Currently: 3 wells, water meets primary drinking water standards Future: 27 wells, require pre and post treatment required from surface water use Bowman

14 Lakehaven Resources: surface water, storm water, ground water and reclaimed water potentially put in the ground Methods: Direct Injection, Surface Spreading and Infiltration Currently Mirror Lake aquifer is full Appendix B, WA DOE

15 Spokane Valley Aquifer 10 Trillion Gallons in volume Deposits range in depth from 150 ft to 600 ft below ground surface Unconsolidated Unconfined Sediment Aquifer Extremely permeable, high in groundwater velocity, susceptible to contamination Composed of Quaternary Age glaciofluvial sediments deposited by floods Edges are Pre-Cambrian metamorphic, Mesozoic and Cenozoic intrusive, and Tertiary Basaltic rocks See source slide

16 Spokane Valley Aquifer See source slide

17 Columbia Plateau Aquifer Semi-Confined Aquifer A semi-confined aquifer is an aquifer underlain by an impermeable stratum and bounded at the top by soil layers of relatively low permeability (hydraulic conductivity), especially in horizontal sense. These layers form the semi-confining layer (the aquitard) in which a free water table is found. Recharge Aquifer Varies areas of the regional areas of the Columbia Plateau receives about six to 25 inches of rainfall annual Do to ground-water pumping the water-level has declined to 300 feet on the interior and declines of more than 100 feet over extensive areas, which has placed important agricultural regions at risk. The water in the aquifer system recharges near the edges of the plateau toward regional drains, such as the Columbia River Vaccaro

18 Columbia Plateau Aquifer Soil Types The Grande Ronde Basalt is the most extensive basalt formation that underlies the Columbia Plateau Miocene basaltic rocks are generally the major aquifers The Miocene basaltic-rock aquifers are as much as 15,000 feet thick in places Unconsolidated-deposit in aquifers are more important than Miocene basaltic-rock in aquifers. For the reason that the hydraulic conductivity of these aquifers is extremely variable but is large enough in places so that the aquifers are productive, especial where they are thick. Vaccaro

19 Puget Sound Aquifer Alluvial and glacial deposits can be more than 3,300ft thick (average 400 ft) Most productive aquifers are sand and gravel from last glaciations Make up top ft of unconsolidated deposits Shallow aquifer makes pollution a danger Pg D17, USGS HA730-H

20 Puget Sound Recharge Recharge estimates based on precipitation, surface geology, land use and cover categories Mean annual recharge ~27 in/year 14,510 ft 3 /s 10,500,000 acre-ft 51% precipitation Fine-grain deposits ~17.6 in/year Course-grained deposits ~35.9 in/year D40

21 Sources Appendix B: Summary of Major ASR Projects in Washington. Washington State Department of Ecology, 2000 Back, William et al. Hydrogeology. Geological Society of America, Inc. Boulder, CO pg 311, 4-11 Bowman, John. Aquifer Storage and Recovery an OASIS. Lakehaven Utility District, Bridge, John S and David W. Hyndman. Aquifer Characterization. Society for Sedimentary Geology Tulsa, OK, 2004 Brown, Chris J. Development of an Aquifer, Storage and Recovery (ASR) Site Selection Suitability Index in Support of the Comprehensive Everglades Restoration Project.U.S. Army Cops of Engineers 2008 Morgan, Laurie. Critical Aquifer Recharge Areas. Washington State DOE: Water Quality Program North Bend Aquifer Testing Going On This Week, Seattle Times. August 30, 1994 Krešić, Neven. Hydrogeology and Groundwater Modeling. Edition 2. CRC Press, 2007 Ponce, Victor M. Sustainable Yield of Ground Water Pyne, R. David G. Groundwater Recharge and Wells: A Guide to Aquifer Storage Recovery CRC Press, 1995 Robins, N. S. Groundwater Pollution, Aquifer Recharge and Vulnerability. The Geological Society; London Vaccaro, John J. and OLSEN, Theresa D., Hydrogeologic Framework of the Puget Sound Aquifer System, Washington and British Columbia. U.S. Geological Survey Philadelphia Annual Meeting (22 25 October 2006) Walla Walla Watershed Planning

22 Sources for Spokane Valley Aquifer Slide 1: o MacInnis, Blake, Painter, Buchanan, Lachaff, Boese, The Spokane Valley-Rathdrum Prairie Aquifer Atlas, pg 3, July 2000 o B Phelps, Local Perspectives on Aquifer Protection, April 1997 o USGS, Assessment of Areal Recharge to the Spokane Valley-Rathdrum Prairie Aquifer, o 2007 Image courtesy of: Spokane Aquifer In-depth, Spokane Aquifer Joint Board, , Slide 2: o Graphs made with data from: MacInnis, Blake, Painter, Buchanan, Lachaff, Boese, The Spokane Valley-Rathdrum Prairie Aquifer Atlas, pg 11, July 2000