Simulating the groundwater discharge to wetlands Mukwonago Basin Example and Potential Application in Dane County
Conceptual Model Topography is major control on flow to wetlands Land Surface Water Table Implication Groundwater discharge is more diffuse and beneath entire wetland WGHNS/USGS/CARPC
Possible Conceptual Model - Lake deposits seal wetland bottom Fibrous Organic Sediment Dense Organic Sediment Lake Silts and Clays Land Surface Water Table Spring at slope toe Implication Seeps and springs in hillslope provide most groundwater to wetlands WGHNS/USGS/CARPC
Conceptual Model - Lake deposits more conductive than organics Fibrous Organic Sediment Dense Organic Sediment Lake Silts and Clays Land Surface Water Table Implication Groundwater discharge is more diffuse and beneath entire wetland. WGHNS/USGS/CARPC
Conceptual Model Piping due to variation in sediments Fibrous Organic Sediment Dense Organic Sediment Lake Silts and Clays Sands and Gravels Land Surface Water Table Implications Discharge is focused in the wetland. WGHNS/USGS/CARPC
From Dane Rollout Event: Bradbury, Parsen, Hunt and Feinstein The county model quantifies groundwater discharge to streams and lakes and routes baseflow downstream Already predicts more discharge around area of interest WGHNS/USGS/CARPC
Proposed Field Investigations Collection of stream and spring flows. Photo: Mike Parsen Spring surveys If spring flows are greater than 0.1 cfs If possible to identify localized discharge. Includes ph, conductivity, Spring Characterization at temperature, photos, Big Keske Spring vegetation, location, and morphology. Stream flow measurements at Starkweather Creek WGHNS/USGS/CARPC
Stream Flow Measurements Existing Proposed WGHNS/USGS/CARPC
Stream Flow Measurements Existing Proposed Dane Spring 14 Database entry Spring located in marsh at west end of Lake Waubesa. Flow cannot be estimated as area abounds with springs. Headwater spring 60' in diameter, approximately 15' deep with flow in excess of 2000 gpm. WGHNS/USGS/CARPC
Mukwonago Basin The Mukwonago River Watershed (MRW) example.. 79 square miles Located in SE Wisconsin Photo from: www.mukwonagoriver.org
Initial Model Development Lake Michigan Basin Parent Model Inset Grandchild Model Inset Child Model (for NAWQA metamodel)
Focus of model: wetlands Bog. Fen Riparian Springs? Peat?
Focus of model: fens
Mapped FENS and SPRINGS Total measured spring discharge=6.62 cfs
Near-surface Flows quantified by UZF package with respect to single MODFLOW water table cell - Infiltration through root zone - Recharge across water table - Rejected Recharge which never enters GW system - Overland Runoff to streams and lakes - Lateral Flow In and Out of water table cell - Upflow toward water table cell - Seepage across water table to land surface Infiltration = sum of Recharge and Rejected Recharge Overland Runoff = sum of Rejected Recharge and Discharge Seepage MODFLOW cell balance= (Recharge + Upflow + Lateral Flow In ) (Lateral Flow Out + Seepage)
Real world setting Near-surface Flows quantified by UZF package
Real world setting simplified with MODFLOW grid Near-surface Flows quantified by UZF package Layer 1 Layer 2 Column 1 Column 2 Column 3
Real world setting further simplified with MODFLOW grid and UZF Package surface undulation representation Near-surface Flows quantified by UZF package Mean Land Surface in Cell Layer 1 Layer 2 Column 1 Column 2 Column 3
Current State of MUK Model Updated Parameters Head and Flux Calibration Simulated water budget for Mukwonago Basin UZF near-surface results Simulated seeps - compared to spring and fen locations Scenario testing POST-SEN-MANUAL-DEL-LK-FINF
Basin Groundwater Budget (cfs) POST-SEN-MANUAL-DEL-LK-FINF
Comparison of Model Seep Locations to Mapped Fens and Springs BASIN Seeps > 0.05 cfs red dots [black outlines fens, yellow=drn, green=sfr] POST-SEN-MANUAL-DEL-LK-FINF
Preliminary MUK SCENARIO TESTING * * POST-SEN-MANUAL-DEL-LK-FINF
Prelim. SCENARIO TESTING POST-SEN-MANUAL-DEL-LK-FINF
From Dane Rollout Event: Bradbury, Parsen, Hunt and Feinstein The county model quantifies groundwater discharge to streams and lakes and routes baseflow downstream Already predicts more discharge around area of interest CARPC/WGHNS/USGS
Questions Lulu Lake Wetlands Bluff Road Spring Pool