Climatic Impacts on Water Resource Sustainability

Richard T. McNiderJohn R. ChristyAbigail Crane

Office of State ClimatologistUniversity of Alabama in Huntsville

64-66”

54-56”

56-58”

58-60”

1941-194319041954 1981

1987-88 2005-062000

Statewide Annual Average Precipitation

Jan-Jun Alabama Rainfall1895-2007

0

10

20

30

40

50

1890 1910 1930 1950 1970 1990 2010

TN ValleyAppalachiansEastern Valleys

Statewide January –July Precipitation

2006

2007

2007 March 850 mb Height Field

Looks like a May Pattern

March Average Climatology

2007 May 850 mb Analysis

Looks like a September/October Pattern

Sustainability

Climate Change

Alabama Statewide Precipitation

Sustainability

Population Growth

With an average annual rainfall of

near 55 inches Alabama receives about 145 million acre-feet of water

annually.

1.0 ft

2.0 ft

3.0 ft

4.0 ft

5.0 ft

Evaporation

Groundwater

Run-off

Evaporation

Groundwater

Run-off

Forest City

Where does Alabama’s Rainfall Go?

Apalachicola – Blountstown 16 million acre-ft/yr

Alabama River -Monroeville 24 million acre-ft/yr

Colorado River – Glen Canyon 10 million acre-ft/yr

River Flows Are Huge in Alabama

Tennessee –Huntsville 30 million acre-ft/yr

Apalachicola

Alabama

Tombigbee

Tennessee

Tombigbee River - Coffeeville 19 million acre-ft/yr

TOTAL MEAN STREAMFLOW ALABAMA RIVER AT CLAIRBORNE L&D1976-2004

0

500

1000

1500

2000

2500

0 2 4 6 8 10 12

Th

ou

san

ds

MONTH(S)

ST

RE

AM

FL

OW

(cfs

)

Alabama has plenty of water availability on an annual basis. Even in the dry years rivers have huge flows compared to western rivers. However, during the summer the consumption of water by the vegetation of the region reduces stream flows to critically low levels.

On-demand (summer

withdrawals) for irrigation may reduce

stream flows to critically low

levels

0

5

10

15

20

25

30

35

40

AL GA FL AZ CA CO

WaterAvailablePublic WaterSupplyI rrigation

Industrial

Annual Fraction of Water Withdrawal in Southeast is Extremely Low

Based on Withdrawals (USGS)

Mil

lio

ns

of

Acr

e-ft

/ye

ar

Net Consumption of Water

2.5%27%

102%

Dr. Ge Sun U.S. Forest Service

0-10% more water available

10-20% more water available

Summary - Sustainability

Climate change and population growth (as we understand it now) do not appear to be a threat to precipitation and overall water quantity.

Urban sprawl and population growth are a threat to water quality.

Population growth may pressure existing water storage and delivery infrastructure in some areas.

What is not sustainable – Alabama’s rain-fed row crop agriculture!

Coastal Plain June Rainfall

0

2

4

6

8

10

12

1895 1905 1915 1925 1935 1945 1955 1965 1975 1985 1995 2005

Inch

es

Corn needs 8-9 inches water to produce maximum yields

Inches

Landowners faced with the competition of Western subsidized irrigated agriculture and deep water holding soils in mid-west resorted to accepting government set asides or timber farming.

Land is now in timber or low intensity pasture.

When a farmer is farming he is turning over $500-$750 per acre per year which is part of the local economy

With timber production he is only turning over $18-39 per acre per year into the local economy.

Rural towns dependent on farming business died out.

The loss of agriculture devastated rural economies

(Birmingham News.Bernard Troncale)

Timberland not necessarily under-taxed it is simply too under-productive

Alabama lost its agriculture largely because it couldn’t compete due to a lack of water for crops.

What if Alabama used its vast surface water to irrigate?

Rio Grande

0.8 million ac-ft/year

Alabama River @ Claiborne

10 to 34 million ac-ft/year

The Alabama River in Monroe County had an annual flow for the driest year on record (2000) of near 10 million acre-ft - 12 times that of the Rio Grande

Yie

ld (

bu/a

c)

Irrigated

Non-Irrigated

9.7” water applied

Acre-ft water can be worth $125 in net profit

Yie

ld (

bu/a

c)

Irrigated

Non-Irrigated

Water Run-off Irrigated Acreage

Sustainable Southeastern Model - Storage of Winter Surface Water – Auburn Larry Curtis Model

Even in dry years crops need less than a foot of water. Irrigation can be supported with a fraction of the winter river flow removed.

Add Water Withdrawal

University Irrigation Study – Sponsored by Senator Shelby with support from Senator Sessions and the Congressional Delegation, Commisioner of Agriculture, ALFA and EDPA.

Includes Auburn, Alabama A&M, Tuskegee, U. of Alabama, UAH

Is investment in irrigation infrastructure the proper choice for Alabama to use its State/County tax credit investment funds and its powerful but limited Congressional initiatives?

Are there agricultural issues, environmental issues and social issues that might limit the potential of irrigation in the State?

This university team is working to provide an interim assessment document to the legislature and the Governor by next January.