GROUNDWATER/SURFACE WATER INTERACTIONS IN TAYLOR SLOUGH EVERGLADES NATIONAL PARK

Transcription

1 GROUNDWATER/SURFACE WATER INTERACTIONS IN TAYLOR SLOUGH EVERGLADES NATIONAL PARK Xavier Zapata-Rios 1,2 René M. Price 1 1 Florida International University 2 Everglades Foundation July 15, 2010

2 Groundwater saltwater intrusion in Taylor Slough SRS-1 LTER sites USGS SH3 SRS-5 SRS-6 USGS SH2 SRS-4 SRS-2 USGS SH1 SRS-3 TS/Ph-1 TS/Ph-2 USGS Groundwater sites 10-15km inland TS/Ph-3 TS/Ph-6 TS/Ph-7 USGS E-146 USGS Upper Taylor Price, Happell, Top, and Swart Use of tritium and helium to define groundwater flow conditions in Everglades National Park. WRR, 39(9): doi: /2002wr

3 Brackish Groundwater discharges to southern Taylor Slough as Coastal Groundwater discharge The brackish groundwater discharge contains high concentrations of P Coastal Groundwater Discharge Price, R. M. P.K. Swart, P.K, and J. W. Fourqurean Coastal Groundwater Discharge - an additional source of phosphorus for the oligotrophic wetlands of the Everglades. Hydrobiologia, 569:

4 Objective of this research: SW GW Quantify GW/SW interactions in Taylor Slough in both time and space

5 4 Methods were used varying with time and space WATER BUDGET HYDRAULIC GRADIENT TEMPERATURE AS A TRACER GEOCHEMISTRY TRACERS

6 WATER BUDGET Inflows Outflows = ΔS P + Qin - ET ± Qout ± ΔS = ± R Conservation of mass P= Precipitation ET= - Evapotranspiration ΔS =Change in storage + Qin= inflow Qout= outflow R= Recharge ASSUMPTIONS No further water exports and imports

7 FLORIDA Atlantic Ocean Watershed Area = 450km 2 80º45 80º30 Golf of Mexico 25º30 Rocky Glades Ingraham Hwy TS C-111 S-332 S-175 S-177 S-178 Homestead Explanation EVERGLADES NATIONAL PARK L31-W C-111E C-110 Taylor Slough boundary S-332 Control structure and number Transects Canals Park Boundary FCE-LTER stations West Lake 25º15 MCC TSPh3 b TSPh6 a b TSPh7 a TRE Little Madeira Bay MUD Discharge stations 0 10 Km Florida Bay

8 WATER BUDGET P + Qin (ET + Qout) = ΔS ± R EVERGLADES NATIONAL PARK N PRECIPITATION Average depth of precipitation was estimated using Thiessen polygons Florida Bay Km

9 Evapotranspiration Penman- Monteith combination equation 67% grassland 33% Mangroves

10 SURFACE WATER INFLOW AND SURFACE WATER OUTLOW TS MCC TRE MUD Taylor River Mouth (TRE) McCormick Creek (MCC) Mud Creek (MUD) TRE

11 CHANGE IN STORAGE 32 Stages TIN is a vector representation made up of irregularly distributed nodes and lines with 3D coordinates. TIN transformed to a Grid 100x100 m

12 HYDRAULIC GRADIENT dh dl Darcy s law for fluid movement piezometer SW GW Kv= 30 cm/day (Harvey et al, 2004) TSPh3 h f = (ρ p /ρ f )h p TSPh6b TSPh7b

13 TEMPERATURE STUDY 107 L Air Water Source: Brodie et al, 2007 Soil Exchange of water between SW and shallow aquifer plays a key role in influencing SW and GW temp.

14 GEOCHEMISTRY AND ENVIRONMENTAL TRACERS Natural chemical and isotopic substances Electrical conductivity ph Temperature Total alkalinity Anions and cations Stable isotopes of oxygen and hydrogen TSPh3 DLT-100 TSPh6b TSPh7b Dionex

15 600 WATER BALANCE RESULTS mm/month Dec-07 Feb-08 Mar-08 May-08 Jul-08 Aug-08 Oct-08 Nov-08 Jan-09 Mar-09 Apr-09 Jun-09 Aug-09 P ET Qin Qout AS R

16 HYDRAULIC GRADIENT RESULTS 5 TSPh6b 0 TSPh6b TSPh7b TSPh3 Stage (cm) NAVD /17/09 05/27/09 06/06/09 06/16/09 06/26/09 07/06/09 07/16/09 07/26/09 08/05/09 SWDock GWC3 TSPh7b

17 HYDRAULIC GRADIENT RESULTS Fluxes calculation TSPh6b Kv= 30 cm/day (Harvey et al, 2004) Positive flux indicates groundwater discharge to Taylor Slough TSPh7b Groundwater fluxes tended to be higher closer to Florida Bay

18 GEOCHEMISTRY AND ENVIRONMENTAL TRACERS Water Balance 80 TSPh6b Recharge Conductivity ms/cm Feb May Jul Oct08 Mar May Jun Jul Sep Nov Jan Mar May-09 Conductivity ms/cm SWMOUTH SWDOCK SWC1 SWC2 GWC1 GWC2 GWC3 TSPh7b 0 1-Jun Jul Sep Nov Jan Mar May-09 SWMOUTH SWCANOE SWA1 SWA3 GWA1 GWA2 GWA3 GWA4 GW discharge is observed when the SW chemistry matches the GW chemistry TSPh6b TSPh7b TSPh3

19 Groundwater Recharge occurs when the soil water temperature mimics the diurnal temp. signal observed in the air and surface water

20 40 June Temperature C Soil temperature is stable at times of groundwater discharge May 2-Jun 7-Jun 12-Jun 17-Jun 22-Jun 27-Jun 2-Jul Surface water Soil Air 34 July 2008 July Temperature C Jun 4-Jul 9-Jul 14-Jul 19-Jul 24-Jul 29-Jul 3-Aug Surface water Soil Air

21 Summary of Results (mm/d) (mm/d)

22 Average R rates in mm/day Water Budget Jan Sep 08 Oct 08 Mar 09 Mar Jul 09 TSPh7b Hydraulic gradient Feb 09 Jul 09 TSPh6b Harvey et al (2002) for the Everglades Nutrient Removal project 0.4 9mm/day and mm/day

23 Conclusions Groundwater discharge accounted for 35% of the input to Taylor Slough Watershed between Jan 2008 and July 2009 Groundwater discharge was highest in July 2008 and May 2009 GWin 35% TSBin 8% Precip 57% Groundwater discharge rates varied from 5 to 18 mm/day