u.s. department of the interior u.s. geological survey water availability, water use, and the great...

U.S. Department of the InteriorU.S. Geological Survey

Water Availability, Water Use, and the Great Lakes Compact

Jim Nicholas, DirectorUSGS Water Science CenterLansing, Michigan

Great Lakes Water Conservation ConferenceMadison Wisconsin October 18-19 2010

Abundance of Water

20 percent of world’s fresh surface water

800,000,000,000,000 cubic feet

Regional bedrock aquifers

Glacial aquifers > 1000-ft thick

100,000,000,000,000 cubic feet

Water Use in Michigan

Michigan is was 8th in population

15th in total water use

33rd in water use per capita

25th in ground-water use

PerspectiveSt. Clair River Flow—121,000 MGDPrecipitation on Lake Michigan—33,000 MGD Evaporation from Lake Michigan—27,000 MGDStreamflow to Lake Michigan—25,000 MGD

Chicago Diversion—2,100 MGDLower Peninsula Groundwater Use—700 MGDPfizer—32 MGDLansing BWL—20 MGDAgricultural Irrigation Well—1 MGDNestle Waters/Ice Mountain—0.36 MGD

Regional abundance gives us our landscape

Makes our lakes Great. Streams too.

But says nothing about how much water is available for human use.

Regional abundance does not mean a lack of local shortagesor competing uses

…consider total assets and cash flow

Competition for water can be regional too

Hydrology and Ecology—A Missing New LinkHydrology is a principal driver of aquatic

ecology

Hydrologists know little ecology and Ecologists know little hydrology

Aquatic ecosystems are a focus of most water availability discussions

How much water do we need to leave in the stream?

There is No Unused Water

All water is being used by someone or something Humans change what the water is being used for

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

Groundwater –Surface WaterA Single Resource

Water Use—Effects on Distribution

Reduced flow to SW—59%

Induced GW flow from outside area—18%

Reduced Storage—11%

Reduced flow to Lake MI—8% Induced flow

from Lake MI—4%

Pumping from Deep Bedrock Aquifer in SE Wisconsin

Sources of Water to Wells

What is Water Use?Detroit land cover change 1905-1992

Changes in land cover affect:

rechargestreamflowwetlandswater quality

What is Water Use?Drain Tiles

Lower water tables

Less recharge

Faster movement to streams

Fewer wetlands

More useable land

Does the amount of a water use matter or just the IMPACT of the use:

changing where water goes, when it goes there, and its quality

Withdrawals and Consumptive Uses:

…no significant individual or cumulative adverse impacts to the quantity or quality of the Waters and Water Dependent Natural Resources of the Watershed

Great Lakes Compact

Michigan’s Water Withdrawal Assessment Tool and Process

• Assist Michigan in implementation of the Great Lakes-St. Lawrence River Basin Compact and Agreement

• Michigan legislation defines and prohibits Adverse Resource Impacts (ARI) to water-dependent natural resources in streams

• Process designed to ensure proposed withdrawals are legal—with burden on proposer

WWAT—Three Models• Flow—How much water is in the stream?

• Withdrawal—How much will a proposed withdrawal reduce streamflow?

• Fish—How will reduced streamflow affect fish?

The WWAT evaluates the impact of the water use, not the amount.

If the impact is not “adverse”, then it is ok

Ecological Response CurvesResponse Curves predict how characteristic fishes will respond to changes in index flow

Development of WWAT• Compact and Michigan Legislation provided

the need to define “adverse” resource impact

• Science provided the context within which to define “adverse”

• State government made policy definition of “adverse”

• Water Resource Conservation Advisory Council provided a collaborative context for policy makers and scientists to iteratively inform each other

Does the amount of a water use matter or just the IMPACT of the use:changing where water goes, when it goes there, and its quality

…then is water conservation also is more than just the amount conserved? Isn’t it about the IMPACT of the conservation?

Water Use and ConservationThe effect matters, not the amount

Conservation is a state of harmony between men and land—Aldo Leopold