FLOOD10516

• County: Delta
• Basin: Gunnison
• Title: North Fork Water Conservancy District Water Management Plan
• Date: 7/1/2001
• Prepared For: Delta County
• Prepared By: Delta Soil Conservation District
• Floodplain - Doc Type: Floodplain Report/Masterplan

North Fork Water Conservancy District - Water Management Plan...

Figure 2-2
Water Budget Concept

Inflows

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Outflows

+

Evaporation
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Canal Seepage
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Crop Requirements
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Field Percolation
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Field Runoff

Headgate Diversions

I Precipitation
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For this water management plan, water budgets were developed for irrigated lands serviced by the Fire
Mountain Canal sinqe the canal irrigates the largest number of acres within the NFWCD. In addition,
available data outside the Fire Mountain Canal service area were more limited. A water budget was
developed for two scenarios; one examined average conditions and the other examined drought conditions.
The average condition scenario is based on average diversion data from 1988 through 1998. The drought
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condition scenario is [based on data from the 1994 drought year.

Water budget result~ are summarized in Table 2-4 and Figure 2-3 for the average scenario; Table 2-5 and
Figure 2-4 for the drought scenario. The following sections discuss the results and describe how the water
budgets were develo'ped.
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Headgate DiverSions
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Table 2-6 and Fig~re 2-5 summarizes Fire Mountain Canal headgate diversions for years 1988 through
1998. The minimym diversions occurred in 1994; the maximum occurred in 1992. Storage and direct
diversions vary from year to year depending on yearly climate conditions (Table 2-6). Over the 11-year
period, total diversions averaged 47,373 acre-feet. Water released from East Beckwith Reservoir No.1
to Fire Mountain Canal amounted to less than 1 percent of average storage diversions.
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Delivery Losse$
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Delivery losses inCluded canal evaporation, canal seepage, and water used by vegetation along the
canal. Delivery lo~ses in the Fire Mountain Canal were originally estimated to be 1 percent per mile of
open canal or 33 percent of headgate diversions (USBOR 1957). Over the years, lining the canal with
concrete or installIng pipe sections has reduced canal seepage. To estimate current delivery losses,
water measurements were recorded along the canal during the most recent irrigation season. Water
measurements wJre taken in the canal at Leroux Creek and downstream at the Fire Mountain Canal
extension. In addition, water measurements were taken for all farm turnouts between these two points.
Delivery losses w~re estimated by subtracting the total flow turned out and flow at the extension from flow
measured upstream at Leroux Creek. Based on these measurements, an estimated 1.71 CFS was lost
for the 1.8 miles of canal between the measurement point, or 0.95 CFS per mile. Extrapolating this loss
estimate for the 29.67 miles of the canal results in 28.18 CFS lost per day, or 55.79 acre-feet per day, or
17 percent of diveisions at a constant diversion flow rate of 165.0 CFS.

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