WSP00392

• File Number: 8276.150
• Description: Grand Valley Unit-Colorado River Basin Salinity Control Project
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 4/1/1992
• Title: 1991 Annual Report: Grand Valley Salinity Control Project Monitoring and Evaluation Program
• Water Supply Pro - Doc Type: Annual Report

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2. Methodoloqy

Data collection and analysis was performed as outlined in the M&E
Annual Report published June 1989. Data was collected on three
separate occasions. Wetland and wildlife habitat were mapped on 77
agricultural units, of which six were irrigation monitoring sites.

Each agricultural unit predominantly consisted of a contiguous farm
unit operated by one individual.

Each inventory determined the quality and quantity of the habitat
for baseline information. Habitat quality included evaluating the
amount of perennial vegetative cover and availability of food and
habitat diversity.

The following habitat types or conditions were mapped and
quantities measured: agricultural crops (by kind), saltbrush,
sagebrush, greasewood, tamarisk, cottonwood, willow, marsh (by
type), and edge (boundaries, field borders, etc.),

Total
were
times

habitat changes due to the on-farm salinity control program
determined, using a ratio of habitat change to acres treated
the total acreage of agricultural unit treated.

Data was analyzed following completion of each sampling cycle and
upon completion of planned salinity control.

In 1988, the M&E Report entitled, "Grand Valley Salinity Control
Project Monitoring and Evaluation Program" stated the agricultural
units were remapped three to five years after installation of
planned practices. This report represents the completion of all
data collection and final analysis for the wildlife habitat
monitoring and evaluation effort as identified in the January 1983
Grand Valley M&E Plan.

3. Results

Data comparison of habitat change from one year after construction
to three to five years after construction showed the following
results. The second sampling cycle (3-5 years after construction)
began in July 1987. Table 9 shows the results of data collected
during that sample period. All 77 agricultural units had
comparative data collected. Cropland decreased 127.3 acres, or
approximately 4.5 percent. Other vegetated non-cropland habitat
types increased 101.6 acres or around 10.6 percent. Most of this
increase is attributed to previously cultivated cropland that was
idle at the time the last monitoring visit was made. The majority
of the idle cropland had grown over to annual and perennial weeds
and was classified as annual herbaceous or perennial herbaceous
habitat types.

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