Ottawa County Water Resources Study Phase 2 Overview David P. Lusch, Ph.D. Department of Geography and Institute of Water Research Michigan State University 1 / 24
Ottawa County Planning and Performance Improvement developed a detailed list of water resource information needs that could inform the decision makers of the county about the sustainability of the groundwater throughout the county. The Phase 2 study has 4 Goals based on these information needs. 4 Goals are specific to Ottawa County 3 other Goals focus on the regional lowlands of Southern Michigan 2 / 24
Goals specific to Ottawa County Goal 1: Quantify the current sustainability of groundwater quantity in the glacial and bedrock aquifers of the county. Goal 2: Quantify the current sustainability of the aquifers of the county based on chloride concentrations. Goal 3: Estimate the future sustainability of the glacial and bedrock aquifers of the county based on projected water quantity and chloride concentrations at 5, 10 and 20 years into the future. Goal 4: Develop and recommend best practices, policies and/or other solutions to address and mitigate any likely groundwater shortages or problematic chloride concentrations that are documented in Ottawa County. 3 / 24
The Phase 2 study will use state of the art modeling software that has been developed at MSU PAWS Process based Adaptive Watershed Simulator IGW Interactive Ground Water 4 / 24
Two model Project Methodology PAWS model for recharge and surface water budget. IGW model for estimating groundwater flow and 3D chloride concentration distribution. 5 / 24
Inputs to the PAWS Model Topography Stream Network, Ponds Land Use /Land Cover Soils Climate Data Streamflows Return flows 6 / 24
Topography (Ottawa Co. LiDAR DEM) 7 / 24
Stream Network, Ponds (National Hydrography Dataset) 8 / 24
Land Use /Land Cover (Ottawa County Impervious map / USDA CDL / USGS NLCD) 9 / 24
Soils (NRCS SSURGO) (micrometers per second) 10 / 24
Precipitation Data (NCDC NEXRAD radar hourly precipitation accumulations for 2013) 11 / 24
Streamflows (USGS + subset of field measurements) 12 / 24
Return flows Discharge from WWTS (Ottawa County Road Commission Public Utilities) Return flow from household septic systems will be incorporated using generalized, published estimates of household water use and maps of non sewered residential areas provided by Ottawa County. 13 / 24
Calibration data for the PAWS Model Streamflows / Baseflows (Measured from 50-60 stream segments) Groundwater Heads (GVSU wells; USGS RASA /MDEQ test wells; MDEQ monitoring wells at sites of environmental concern) Glacial RASA Rock/Deep Model cell resolution will be 300 m x 300 m (~ 22 acres). 14 / 24
Outputs from the PAWS Model Recharge to the water table aquifer (input to IGW) Water Balance of the Glacial Aquifer Detailed maps of: Evapotranspiration (ET) Infiltration Runoff Recharge Streamflows Soil Moisture Depth to the water table Spatial resolution of outputs for management support is 1000 m x 1000 m (about 250 acres) 15 / 24
IGW Interactive Ground Water An integrated groundwater modeling suite utilizing a powerful parallel computing methodology with computational steering and interactive visualization to provide dynamic groundwater flow modeling. IGW supports interactive, hierarchical, multi scale groundwater flow modeling. 16 / 24
Inputs to IGW 3D Hydraulic Conductivity (transition probability model) Bedrock framework (MDEQ GWIM database + USGS RASA reports) 17 / 24
Inputs to IGW Stream network (National Hydrology Database) Lakes/ponds (from Michigan Geographic Framework) Digital elevation model (LiDAR from Ottawa County GIS) Recharge (from PAWS model) Water use (from MDEQ / MDARD Water Use Program) Initial Cl concentrations (water samples from volunteer homeowners + some Ottawa County Health Department data) 18 / 24
Ottawa County Phase II Water Resource Study Chloride Sampling Volunteer Locations (09/12/2014) 254 volunteer sites 99 shallow glacial aquifer 22 deep glacial aquifer 133 bedrock aquifer 19 / 24
Calibration Data for IGW Baseflow, synoptic (from streamflow measurements on all stream segments) Baseflow, time series (12 monthly streamflow measurements on 15 streams) Static water levels (GVSU wells, MDEQ monitoring wells and aquifer tests, USGS RASA data) Static water level and Cl concentration time series (from the single test well and two monitoring wells (4 day pumping stress period; 2 week recovery period) Model cell resolution will be 300 m x 300 m (~ 22 acres). 20 / 24
Outputs from IGW Aquifer Depth and Thickness Maps and 3D Graphics Static Water Level Maps and 3D Graphics Glacial and Bedrock Aquifer Groundwater Flow Maps Groundwater Discharge to Streams Map Current Water Quantity Severity Rating Map(s) Chloride Depth Map(s) and 3D Graphic(s) Chloride Concentration Map(s) Chloride Migration Analysis Results Current Chloride Severity Rating Map(s) 21 / 24
Outputs from IGW Maps of Projected Change in Groundwater Quantity at 5, 10, and 20 years Maps of Projected Change in Chloride at 5, 10, and 20 years Projected Groundwater Quantity Severity Rating Map(s) at 5, 10, and 20 years Chloride Rating Maps at 5, 10, and 20 years Spatial resolution of outputs for management support will be 1000 m x 1000 m (about 250 acres) 22 / 24
Milestones & Timeline 2014 Sept - Oct: Countywide Water Sampling (Cl levels from 500 wells) Sept - Oct: Streamflow Measurements (80+ streams) Oct - Nov: Recovery of SWL data from MDEQ monitoring wells Oct - Nov: Bedrock Aquifer Pumping Test 2015 Jun: Countywide Recharge Modeling completed Aug: Statewide Groundwater Assessment completed 2016 Mar: Countywide Groundwater Quantity Modeling completed Sept: Countywide Groundwater Chloride Modeling completed Dec: Future Sustainability Modeling completed 2017 Jun: Hotspot Quantity & Quality Modeling completed Jun - Jul: Revised Web-based DSS completed / training offered Aug: Final Report completed 23 / 24
Interactive Water Resource Decision Support System 24 / 24
Partnership List
Groundwater Task Force Members
Ottawa County Water Resources Study Phase 2 Overview 27 / 24