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Reduced Phosphorous, Sediment,
and Nitrogen
Lake Erie/Maumee River Basin
Water Quality
Improvement
Delivery of total phosphorus from the Maumee River watershed to Lake
Erie dropped 20 to 25 percent, and dissolved phosphorus – the form
most available to algae – fell 60 to 70 percent during the 1975-1995
cleanup efforts in the Lake Erie basin. Suspended sediment is
substantially lower now than in 1975, and total Kjeldahl nitrogen is
down.
Watershed Description
The Maumee River watershed
drains a total of 6,608 square miles (4.2 million acres) in Ohio,
Indiana and Michigan. The LEASEQ water quality study collected samples
at Waterville, Ohio, which accounts for 6,329 square miles (4.0
million acres). Agricultural land accounts for 88 percent of the land
use in the watershed in the test area.
The Maumee River basin was designated
one of 43 Areas of Concern in the Great Lakes basin in 1985: though it
carries only three percent of Lake Erie’s water, it contributes
significant portions of the phosphorus and sediment entering the lake.
The Partnership
A wide variety of programs
promoting best management practices (BMPs) such as conservation
tillage and fertilizer management have been implemented in the Maumee
River watershed. Agencies including the U.S. Environmental Protection
Agency (EPA), Ohio EPA, Ohio Department of Natural Resources, USDA
Natural Resources Conservation Service, local soil and water
conservation districts, and university advisors – and their
counterparts in Indiana and Michigan – a played major roles in
improving water quality in the basin.
How They Did It
Demonstration plots,
educational efforts promoting BMPs, mandatory upgrades of wastewater
treatment facilities, and a cost-share program to encourage area
farmers to buy or build conservation tillage equipment led to
significant increases in BMP adoption. For instance, 1.6 million acres
in the LEASEQ study area is in conservation tillage, which reduces
runoff of sediment, nutrients and pesticides. In addition, thousands
of farmers have reduced their applications of phosphorus and nitrogen
fertilizers. The result: significant improvements in water quality.
Suggestions for
Others
According to Dr. David
Baker of Heidelberg College in Tiffin, Ohio, who participated in the
LEASEQ study, the first thing to note is that BMPs work in large
watersheds – but it can take 10 to 20 years to see the results.
Baker also recommends keeping approaches and goals flexible. He notes
that early conservation tillage approaches were aimed at corn crops,
but turned out to be better suited – and widely accepted – in
soybeans instead. In addition, though early BMP programs focused
exclusively on conservation tillage, reduced fertilizer use also
played an important role in improving water quality – an
illustration of the importance of widening the scope of BMPs where
necessary.
Contacts
Dr. David Baker
Water Quality Laboratory
Heidelberg College
310 East Market Street
Tiffin, Ohio 44883
(419) 448-2201 phone
(419) 448-2345 fax
dbaker@mail.heidelberg.edu
Dr. Peter Richards
Water Quality Laboratory
Heidelberg College
310 East Market Street
Tiffin, Ohio 44883
(419) 448-2198 phone
(419) 448-2345 fax
prichard@mail.heidelberg.edu
Note:
USDA’s
Lake Erie Agricultural Systems for Environmental Quality (LEASEQ)
program allowed researchers to study changes in water quality
resulting from BMPs over a 21-year period, from 1975 to 1995.
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