GROUNDWATER/SURFACE-WATER EXCHANGE AND THE EFFECTS ON SURFACE WATER QUALITY AND QUANTITY IN THE MISSISSIPPI DELTA

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1 GROUNDWATER/SURFACE-WATER EXCHANGE AND THE EFFECTS ON SURFACE WATER QUALITY AND QUANTITY IN THE MISSISSIPPI DELTA Jeannie R.B. Barlow U.S. Geological Survey Mississippi Water Science Center Jackson, MS

2 Mississippi Delta (not the MS River Delta)

3 Land of cotton, blues, and rock & roll

4 Lower Mississippi River Flood Plain Altered Mississippi River Flood Plain Land Characterization: Bottomland hardwood wetlands Annual flooding distributes nutrient-rich matter Introduction and Study Area Logged, drained, channelized Levees built Land Characterization: > 80% Agriculture Row crops Rice Aquaculture

5 John James Audubon Referring to the Yazoo River Audubon described it thus: a beautiful stream of transparent water, covered by thousands of geese and ducks and filled with fish

6 In the Louisiana Canebrakes (Roosevelt, 1908) Roosevelt describes a virtual wilderness, with old growth forest and wetlands dominating the landscape with a few farms hacked out of the forest. He describes canebrakes 20 feet tall extending for miles and the bayous teaming with alligator, garfish, and monstrous snapping turtles, fearsome brutes of the slime

7 Estimated Withdrawals in MGD Water Availability: Alluvial Aquifer Alluvial extent Agriculture / Irrigation 3 rd most intensively used aquifer in US in 2000 MS 2 nd largest user behind AR Arkansas MS Alluvial aquifer Cone of Depression Louisiana Mississippi 2000 Estimated Withdrawals ft Gravel/Sand MRVA - TN MRVA - LA MRVA - MO MRVA - MS MRVA - AR

8 Water-Level Elevation (ft abv lsd) Water Availability: Alluvial Aquifer Taken from Barlow and Clark, 2011

9 How has flow in the alluvial aquifer changed over time? Conditions in 1870 (Predevelopment) Recharge Conditions in 2007 Recharge Discharge to wells Mississippi River Bluff Hills Mississippi River Bluff Hills Underlying Units Stream Leakage Underlying Units Stream Leakage Total In = Total Out = Net Storage Gain = Total In = 0.49 Total Out = 2.20 Net Storage Loss = 1.71

10 NAWQA ACT Study

11 Groundwater/Surface-Water Exchange 1. Quantify GW/SW exchange Does gw/sw interaction occur at the site? What is the lateral extent of exchange? What is the prominent direction of exchange? What is the net exchange? 2. Determine effects of exchange on water-quality How do sw and gw quality compare to one another? How does gw/sw interaction affect the transport of certain constituents?

12 Bogue Phalia Basin and Heat Tracer Site Bogue Phalia Basin and Heat Tracer Site 12 D E L T A Mississippi River Rosedale Cleveland Bogue Phalia Bogue Phalia!P Leland!P+U!P!P!P Greenville Indianola Kilometers 4 Leland Kilometers!P+U!P!P!P!P Piezometers Gage downstream Observation Well 10/11/2012

13 Bogue Phalia Heat Tracer Transect Left Channel Flow direction Center Right Channel 10/11/2012

14 Depth below Streambed [m] Piezometer Installation and Instrumentation C C L20 C L50 C100 R L100 R C L200 R Distance [m] 10/11/2012

15 Methods: Heat Tracing Losing Stream: h bot h top = -dh Gaining Stream: h bot h top = +dh -dh dh 0.3 h top h bot h bot h top R50 R R100 R R200 R /11/2012

16 Methods: Energy (Heat) Transport Solute Transport Advection fluid movement Dispersion concentration gradients ( high to low) and pore space HIGH/HOT Energy Transport Advection fluid movement Conduction temperature gradients (hot to cold) LOW/COLD 10/11/2012

17 2005 Hurricane Season Hurricane Katrina August 2005 Hurricane Rita September 2005

18 TEMPERATURE, IN DEGREES CELSIUS STAGE, IN FEET ABOVE DATUM Hurricane Katrina GAINING GAINING LOSING 2.7 m /16/2005 9/17/2005 8/16/2005 0:00 8/20/2005 0:00 8/24/2005 0:00 8/28/2005 0:00 9/1/2005 0:00 9/5/2005 0:00 9/9/2005 0:00 9/13/2005 0:00 10/11/2012 9/17/2005 0:00

19 Katrina: Temperature Contours Stage = 2.7 m (9 ) Stage = 5.3m (17.4 ) 10/11/2012

20 TEMPERATURE, IN DEGREES CELSIUS STAGE, FEET ABOVE DATUM Hurricane Rita GAINING LOSING m GAINING /20/ /10/2005 9/20/2005 9/22/2005 9/24/2005 9/26/2005 9/28/2005 9/30/ /2/ /4/ /6/ /8/ /10/200 0:00 0:00 0:00 0:00 0:00 0:00 0:00 0:00 0:00 0:00 5 0:00 10/11/

21 Rita: Temperature Contours Stage = 2m (6.6 ) Stage = 7.3m (23.84 ) 10/11/2012

22 Boundary Conditions CONSTANT HEAD (h top ) - derived Specified Temperature measured (Stream Tidbit) h bot dh h top m NO FLOW NO FLOW C50 C100 R50 R L100 Specified Temperature measured (200 cm Tidbit) CONSTANT HEAD (h bot ) - derived 1 m L200 R200 10/11/2012

23 GW/SW Exchange Left Channel K=8.1X10-6 m/s Left Channel K=9.1X10-6 RightChannel K=1X10-5 m/s Right Channel K=2.1X10-5 m/s Gage Height (m) /11/ /7/ /4/ /11/2012 Stage (m) Flux, m/d 0

24 GW/SW Exchange Table 4. Maximum Discharge and Cumulative Volume moving through each 1 m 2 monitoring point and Bogue Phalia gaging station for Hurricanes Katrina and Rita. Station Max Discharge Katrina: 8/29/2005-9/7/2005 Rita: 9/24/ /10/2005 Max Cumulative Discharge Cumulative Percent of Percent of total (m 3 /d) Volume (m 3 ) total Flow (m 3 /d) Volume (m 3 ) Flow Bogue Phalia near Leland Left Channel K=8.1E-6 m/s Left Channel K=9.1E-6 m/s Right Channel K=1.1E-5 m/s Right Channel K=2.1E-5 m/s Table 5. Estimates of cumulative volume moving through 25 m by 40 m reach and Bogue Phalia gaging station for Hurricanes Katrina and Rita. Katrina: 8/29/2005-9/7/2005 Rita: 9/24/ /10/2005 Station Cumulative Volume (m 3 ) Percent of total Flow Cumulative Volume (m 3 ) Percent of total Flow Bogue Phalia near Leland BPTR1 25 m Reach /11/2012

25 25 10/11/2012

26 Elevation (m) 2.25 m 3.15 m VS2DH Variable Saturated 2-D Heat/Flow Model West All Boundaries: Observed Head and Temperature using 1 Day Recharge Period East RB100 H: HECRAS Model using gage T: Stream gage Medium Sand LB100 RB150 RC100 obs CC100 obs Clay LC100 obs LB150 RB200 LB-200 RC200 CC200 LC m Horizontal Distance (m)

27 3.15 m 3.15 m Heterogeneous Streambed Flux Patterns Temperature, C Temperature, C West Gaining Stream Percentage of Time Gaining : 56 Mean Residence Time: 4.4 d (105.6 h) per unit streambed East Total = -5,639 m 3 Total = 330 m 3 Total = -274 m 3 Streambed Total = 6,077 m 3 Total = -1,262 m 3 Total = 318 m 3 Total = -893 m 3 Total = 304 m 3 Losing Stream West Percentage of Time Losing : 44 Mean Residence Time: 0.5d (12 h) per unit streambed Total = 17,174 m 3 Total = 17,277 m 3 East Total = 1,151 m 3 Streambed Total = -17,453 m 3 Total = -18,729 m 3 Total = 228 m 3 Total = m 3 40 m Total 249m 3

28 Streambed Flux (m 3 /d) Gaining Losing flux through streambed (m 3 /d) Nitrate Concentrations Nitrate (mg/l) in stream (mg/l) Streambed Flux and Water Quality Stream NO 3- Concentrations higher during losing periods Never detected at 2 m beneath streambed throughout study Flux through streambed: losing flux >> gaining flux Cumulatively a losing stream at this site

29 Altitude (m) Nitrate removed from stream water moving through anoxic streambed during losing conditions 36 FS3 FS2 FS1 AR1 34 Clay Losing Stream Stage 32 Clayey sandy silt Oxic stream water with nitrate Clay Clayey sandy silt 30 Fine sand RB RC CC LC LB Fine sand 28 Gaining Stream Stage 26 Medium sand 24 Medium sand Anoxic groundwater without nitrate FE(III)/SO4 reducing conditions Distance (m)

30 Streambed Flux coupled with stream NO 3 data to estimate amount removed during losing conditions Nitrate Flux (MT/d) SW Daily NO3 Flux (MT) Daily NO3 flux in stream = stream Q * stream NO 3 concentration Streambed NO3 Daily Flux (MT) - 1 km Reach Daily NO3 flux removed through streambed = losing streambed flux * stream NO 3 concentration For a 1 km reach of stream, 5% of the total nitrate load in the stream is removed by streambed processes over 18 month study period Daily nitrate flux in the stream Estimated daily nitrate flux removed by streambed processes over a 1 km stream reach Daily NO 3 concentrations estimated from discrete data using USGS regression program, LOADEST

31 Total Nitrogen Yields delivered to the Gulf of Mexico Bogue Phalia and Big Sunflower Basins Taken from:

32 Real-time coupled groundwater streamgaging stations (MT, WY, and MS Pilot Study) Study Objective Assess the role of groundwater/surface-water exchange on the transport of nutrients in the northwestern MS Assess the feasibility of monitoring groundwater/surface-water exchange at existing streamgaging locations 4 piezometers installed July 2010 near existing stream gages Big Sunflower at Clarksdale Big Sunflower at Sunflower Big Sunflower at Anguilla Little Sunflower Diversion Canal

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34 East Existing Gage House: Stage and Stream Temperature DCP to relay transducer data West 1 to 1 ¼ diameter PVC pipe ~35 Groundwater level 21.5 Stream Stage Pressure Transducer: Head Conductance, and Temperature *not to scale

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36 Water-Level Elevation, feet above msl West 41.5 DCP to relay transducer data Deck for access during high flow ~100 Existing Gage House: Stage, Conductance, and Stream Temperature East 2011 Mississippi River Basin Flood: Groundwater/Surfacewater response in the Mississippi Delta 115 *not to scale Pressure Transducer: Head Conductance, and Temperature 110 GW/SW Exchange 105 Site located in middle of alluvial aquifer cone of depression groundwater levels typically more than 10 feet below streambed Flood induced stages increased GW/SW exchange to the point that groundwater levels were above the streambed Streambed Stream Stage Groundwater Level

37 Recent and potential uses for real-time groundwater monitoring at streamgages Recent Uses: Illustrating the effects of irrigation practices on local groundwater levels Early warning of flooding due to rapidly rising groundwater caused by infiltration from a stream Determining an estimate of stream stage at sites where streamgages are damaged by floods Understanding of the groundwater/surface-water interaction and how changes to any part of the system such as a weir installation, effect the dynamic Potential uses: Understanding impacts of groundwater/surface-water exchange on fisheries and other aquatic populations Managing of irrigation practices to minimize effects on instream flows to reduce potential impacts on endangered species Estimating water fluxes across the streambed using water-level/temperature-based simulations Real-time modeling of chemical fluxes moving between the groundwater into streams Pairing with existing groundwater wells in a watershed to understand ecosystems dynamics and water exchange

38 Summary GW/SW exchange occurs regularly at study transect and the extent of exchange extends laterally into MRVA Redox conditions appear to prevent transport of agricultural chemicals Groundwater/surface-water exchange removes nitrate in surface-water GW recharge to stream aids in dilution of agricultural chemicals in stream Groundwater/surface-water exchange is heterogeneous in the Delta and many streams have lost connection with the aquifer Real-time groundwater/surface-water networks aid in monitoring the connection between streams and the aquifer

39 Thank-you! 39 Recent Publications Barlow, J.R.B, Kingsbury, J.A., and Coupe, R.H., 2012, Changes in shallow groundwater quality beneath recently urbanized areas in the Memphis, Tennessee Area, accepted - Journal of the American Water Resources Association Barlow, J.R.B., and Coupe, R.H., 2012, Groundwater and surface-water exchange and resulting nitrate dynamics in the Bogue Phalia Basin in northwestern Mississippi. J. Environ. Qual. 41: Barlow, J.R.B., and Clark, B.R., 2011, Simulation of water-use conservation scenarios for the Mississippi Delta using an existing regional groundwater flow model: U.S. Geological Survey Scientific Investigations Report , 14 p. Barlow, J.R.B., and Coupe, R.H., 2009, Use of heat to estimate streambed fluxes during extreme hydrologic events. Water Resources Research. Vol. 45, W01403, DOI: /2007WR Bryson, J.R., Coupe, R.H., and Manning, M.A., 2007, Characterization of Water Quality in Unmonitored Streams in the Mississippi Alluvial Plain, Northwestern Mississippi, May-June 2006, U.S. Geological Survey, Scientific Investigations Report , # p. Bryson, J.R, Blasch, K.W., Hoffmann, J.P., 2006, A Local Meteoric Water line and Isotope-Elevation Gradient Relations for the Upper and Middle Verde River Watersheds: Southwest Hydrology, January/February Bryson J.R., 2005, Determination of Ground-water Flow Paths Using Stable Isotopes as Geochemical Tracers: Upper and Middle Verde Watersheds, Arizona, USA: Master s Thesis, University of Arizona, /11/2012