Estimating Additional Water Yield from Changes in Management

• File Number: 8461.250
• Description: Water Issues
• State: CO
• Basin: South Platte
• Water Division: 1
• Date: 5/12/2000
• Author: Charles A. Troendle, James M. Nankervis
• Title: Estimating Additional Water Yield from Changes in Management
• Water Supply Pro - Doc Type: Report/Study

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decrease in flow; the question is whether or not the change can be detected
-at an off-site streamgage.
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Cumulative North Fork Water Yield (in)
Figure 10: Cumulative annual water yield for Brownie Creek ploued over that for North Fork
of Dry Creek. The Brownie Creek streamgage was relocated in 1960. Harvest
occurred on Brownie Creek from 1960-1972 and effect is not evident
- As noted earlier, the primary objective of this effort is to address the
application of existing water yield augmentation technology to the "suitable
and treatable" NFS land in the North Platte River Basin and quantify the
potential for augmentation through timber harvest. At the outset, it should be
noted that even Coon Creek, where water yield augmentation was the
primary focus and dedicated use of the land, less than 24 percent of the total
watershed area could be impacted. The initial intent was to harvest one-third
of the watershed area in order to mimic the experimental watershed
treatments. Even though the Coon Creek project was minimally constrained
by concern over other resources, operational constraints in the forest plan
limited the harvested area to less than 24 percent of the watershed area.
In managing public lands, the USFS must address the potential impact of
any proposed alternative on numerous resources. Figure 11 represents a
simple schematie showing the relative impact of various harvesting practices
on the value of various resources, including water. There are tradeoffs, and
as can be inferred from Figure 11, not all resource needs can be met on a
given site. Patch clear cutting (PC), for example, appears to maximize water
?yield, , but it is very detrimental to several other resources
currently considered important. Patch clear cutting cannot be aPPlied to all
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