Debunking Water Myths and Misconceptions The Role of Science
MWEA 84th Annual Conference June 21-24 Boyne Falls Jim Nicholas, Center Director USGS Michigan Water Science Center U.S. Department of the Interior U.S. Geological Survey
Myths and Misconceptions Water is in compartments—boundaries. Groundwater doesn’t move. Weather should be like when I was a kid. What’s normal? There’s plenty of water for any use.
What is water use? We understand water in Michigan very well.
BOUNDARIES Boundaries aren’t real Groundwater is always flowing to surface water
Hydrologic Cycle Precipitation
Streamflow
Groundwater
Evaporation
Compartments are convenient ATMOSPHERE
SURFACE WATER
GROUNDWATER
Boundaries are perception, not reality Air Lake
Wetland
Groundwater
Groundwater-Surface Water A Single Resource—no boundaries
Groundwater—Storage and Distribution
Groundwater Distribution Groundwater is always moving Naturally moves to surface water
Groundwater—floats your kayak in the summer
Groundwater-Surface Water Groundwater always part of the flow in most rivers Many times it is the only flow
Groundwater-Surface Water 25 75 28 72
35 65
Ground water in blue
21 48
79
52
VARIABILITY My experience and knowledge What’s “normal”?
Precipitation—varies in space
Runoff—varies in space
Streamflow—varies in space
Glacial Aquifer Yields— vary in space
Not all Great Lakes levels are high or low at the same time
Great Lakes Water Balance
Evaporation from Lake Superior— seasonal variability
Streamflow Hydrograph
Two years compared to a 54-year average— Clinton River
Streamflow Hydrograph
Are low flows increasing in the Clinton River?
Groundwater-Level Hydrographs Oct
June
Compare 1979-92 (black) with 2000-03
Sep
Lake Superior Water Levels—1860-2000
Lake Superior Water Levels— last 5000 years
Climate—last 120 years of temperature change
WATER AVAILABILITY Atlanta Abundance What about quality? What is water use? Who needs water?
Abundance of Water 20 percent of world’s fresh surface water
3288 miles of coastline to access it Regional bedrock aquifers
Glacial aquifers > 1000-ft thick Blue Ribbon trout streams
Water Use Michigan is 8th in population 15th in total water use
33rd in water use per capita 25th in ground-water use
Perspective St. Clair River Flow—121,000 MGD Precipitation on Lake Michigan—33,000 MGD Evaporation from Lake Michigan—27,000 MGD Streamflow to Lake Michigan—25,000 MGD Lower Peninsula GW Recharge—16,000 MGD Chicago Diversion—2,100 MGD Lower Peninsula Groundwater Use—700 MGD Pfizer—32 MGD Lansing BWL—20 MGD Agricultural Irrigation Well—1 MGD Nestle Waters/Ice Mountain—0.36 MGD
Regional abundance does not mean a lack of local shortages or competing uses …consider total assets and cash flow
Quantity includes Quality sometimes the problem is natural
Quantity includes Quality sometimes the problem is very long-term
Pathways—A key to management
Quantity includes Quality Ground-Water Discharge through Streambed Sediments Attenuates Sediment Temperature
There is No Unused Water All water is being used by someone or something All human use of water has an effect on someone or something—often local Often the effect is not noticeable or is perceived to be outweighed by a benefit (Chicago Diversion)
There is No Unused Water Human uses of water redistribute water in time and place A dam may alter the high and low flows of a river A city with an intake in a Great Lake may discharge used water to a stream that is tributary to the lake A groundwater use will always have an effect on a surface-water body, though the effect may be too small to measure
Water Use—Effects on Storage and Distribution
Water Use— Effects on Storage
Water Use—Effects on Distribution Pumping from Deep Bedrock Aquifer in SE Wisconsin Reduced flow to Lake MI—8%
Induced flow from Lake MI—4%
Reduced Storage—11%
Induced GW flow from outside area—18%
Reduced flow to SW—59%
Sources of Water to Wells
Uses can affect ecosystems New State Law— Links Use and Ecosystem
Source of Water to Wells Begins all storage (lower water level) Ends all captured streamflow
Irrigation Water Use— varies in space + time Ground water 64%
Surface water 34% Great Lakes 2%
What is Water Use? Detroit land cover change 1905-1992 Changes in land cover affect: recharge streamflow wetlands water quality
What is Water Use? Drain Tiles Lower water tables Less recharge Faster movement to streams Fewer wetlands More useable land
A new use for groundwater
Hydrology and Ecology— A Missing Link Hydrology is a principal driver of aquatic ecology
Hydrologist know little ecology and Ecologists know little hydrology Very little known about ecosystem dependence upon hydrology
Debunked Myths and Misconceptions Boundaries are perception, not reality Groundwater is always moving to surface water The hydrologic cycle has a lot of variability in a year, decade, century, and millenia—it is very hard to define “Normal” There is no unused water Our uses of water and land redistribute water temporally and spatially We need to understand pathways to manage resources—science needs to inform management and policy
mi.water.usgs.gov
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