Embed Size (px)
Citation preview
1 / 14David P. Lusch, Ph.D.
David P. Lusch, Ph.D.Distinguished Senior Research Specialist
Michigan State UniversityDept. of Geography, Remote Sensing & GIS
Research and Outreach Services Group
Institute of Water Research
Michigan’s Michigan’s WWater ater WWithdrawal ithdrawal AAssessment Process ssessment Process
andand Using the WWA Tool for Planning Using the WWA Tool for Planning
and Watershed Managementand Watershed Management
and
2 / 14David P. Lusch, Ph.D.
Michigan’s Water Withdrawal Assessment Process Michigan’s Water Withdrawal Assessment Process for Planning and Watershed Managementfor Planning and Watershed Management
• The Great Lakes Compact: why Michigan is regulating large-quantity water withdrawals
• Brief review of Michigan Water Law
• Tutorial on some key hydrologic terms and concepts
3 / 14David P. Lusch, Ph.D.
•Sources of Water in Rivers
– Overland Flow
– Baseflow (i.e., groundwater discharge)
– Interflow
– Direct precipitation in channel
Michigan’s Water Withdrawal Assessment Process Michigan’s Water Withdrawal Assessment Process for Planning and Watershed Managementfor Planning and Watershed Management
4 / 14David P. Lusch, Ph.D.
•Sources of Water in Rivers
Precipitation
ET
Groundwater
Groundwaterflow path
Soil Moisture
Infiltration
Overland Flow (runoff)
InterflowWater table
Michigan’s Water Withdrawal Assessment Process Michigan’s Water Withdrawal Assessment Process for Planning and Watershed Managementfor Planning and Watershed Management
5 / 14David P. Lusch, Ph.D.
•Baseflow of a river
−the amount of groundwater that discharges from an aquifer into the watercourse.
−Baseflow occurs year-round, but fluctuates seasonally depending on the level of the water-table aquifer.
−The baseflow of a river is supplemented by direct runoff during and immediately after precipitation or snowmelt events.
Michigan’s Water Withdrawal Assessment Process Michigan’s Water Withdrawal Assessment Process for Planning and Watershed Managementfor Planning and Watershed Management
6 / 14David P. Lusch, Ph.D.
Runoff dominated river – very little baseflow: “flashy” and warm
Intermediate river – baseflow + runoff: warm/cool, but fewer extremes
Baseflow dominated river – very little runoff – cold/cold transitional
Michigan’s Water Withdrawal Assessment Process Michigan’s Water Withdrawal Assessment Process for Planning and Watershed Managementfor Planning and Watershed Management
7 / 14David P. Lusch, Ph.D.
• Index Flow
– the flow that is met or exceeded 50% of the time for the lowest summer flow month of the flow regime, determined over the period of record or extrapolated from USGS flow gauges in Michigan.
Michigan’s Water Withdrawal Assessment Process Michigan’s Water Withdrawal Assessment Process for Planning and Watershed Managementfor Planning and Watershed Management
8 / 14David P. Lusch, Ph.D.
•Groundwater Withdrawal Impacts on Rivers
– Reduced flow
– Altered water temperatures
Michigan’s Water Withdrawal Assessment Process Michigan’s Water Withdrawal Assessment Process for Planning and Watershed Managementfor Planning and Watershed Management
9 / 14David P. Lusch, Ph.D.
•GW Withdrawal Impacts on Rivers
Precipitation
ET
Groundwater
GroundwaterFlow - COLD
Soil Moisture
Runoff - WARM
InterflowWater table
ReducedBaseflow
Michigan’s Water Withdrawal Assessment Process Michigan’s Water Withdrawal Assessment Process for Planning and Watershed Managementfor Planning and Watershed Management
10 / 14David P. Lusch, Ph.D.
• Pumping well water sources
– Initially, water is removed from storage in the aquifer, and the head near the well is reduced inducing flow towards the well.
– As water is removed from storage, a cone of depression forms around the well.
Michigan’s Water Withdrawal Assessment Process Michigan’s Water Withdrawal Assessment Process for Planning and Watershed Managementfor Planning and Watershed Management
11 / 14David P. Lusch, Ph.D.
• Pumping well water sources– In most cases, the cone of depression
continues to expand until the pumpage is balanced by a decrease in discharge from the system, resulting from the lowered head in the system which decreases the flow gradient in discharge areas and may shift the groundwater divide.
– The change in discharge due to pumping is called “capture.”
Michigan’s Water Withdrawal Assessment Process Michigan’s Water Withdrawal Assessment Process for Planning and Watershed Managementfor Planning and Watershed Management
12 / 14David P. Lusch, Ph.D.
Michigan’s Water Withdrawal Assessment Process Michigan’s Water Withdrawal Assessment Process for Planning and Watershed Managementfor Planning and Watershed Management
Source of water to a pumping well
Decrease in the discharge from
the system, resulting from the
lowered head in the system, decreased
gradients in discharge areas and shifts in the
groundwater divide.
Ground-waterdivide
Gro
un
d-w
ater
div
ide
Cone ofdepression
Q2 > Q1
gainingstream
streamgainsless
losingstream
13 / 14David P. Lusch, Ph.D.
Michigan’s Water Withdrawal Assessment Process Michigan’s Water Withdrawal Assessment Process for Planning and Watershed Managementfor Planning and Watershed Management
• Source of water to a pumping well
14 / 14David P. Lusch, Ph.D.
• The next segment
– Water Withdrawal Tool Science
Michigan’s Water Withdrawal Assessment Process Michigan’s Water Withdrawal Assessment Process for Planning and Watershed Managementfor Planning and Watershed Management
