WSP00209

• File Number: 8460.500
• Description: Platte River Recovery Plan
• Basin: South Platte
• Date: 5/30/2000
• Author: CWCB
• Title: Draft Water Action Plan
• Water Supply Pro - Doc Type: Publication

Table 111-18

Land FaIlowinl! - Reductions in Consumptive Use (ae-ft)
Month Reach 10 Reach 14 Reach 15 Reach 16 Reach 17 Reach 18 Reach 19
October 0 0 0 0 0 0 0
November 0 0 0 0 0 0 0
December 0 0 0 0 0 0 0
January 0 0 0 0 0 0 0
February 0 0 0 0 0 0 0
March 0 0 0 0 0 0 0
April 5 7 6 6 10 8 3
May 10 16 13 12 24 18 7
June 89 107 119 139 267 326 285
July 210 246 282 342 775 976 817
August 188 221 253 315 625 791 705
September 15 23 18 24 44 44 29
Annual 517 619 690 839 1744 2164 1846

OPtion 4: Changes in Irrigation Techniques

In Reaches 17, 18, and 19 a large portion of return flows return to the Republican River
Basin, accrete to the groundwater mound or return to the Platte Ri ver below the critical
habitat. It was assumed that 50 percent of the return flows do not return to the Platte
River above the critical habitat. A 1993 survey conducted by CNPPID indicated that
about 50 percent of the surface supplied irrigated acreage within their district is irrigated
with techniques that have substantial potential for increases in efficiency. The distribution
of land involved in each reach was based on the distribution of acres irrigated with
surface supplies. The number of acres that were assumed to be included in this program
are summarized in the following table.

Table III-19
Chan es in Irri ation Techni ues
Acres Included in
Pro ram (ac)
6,800
8,700
7,400
22,900

Reach
17
18
19
Total

The tables below show the proposed average monthly reductions in diversions and the
reductions in on-farm deliveries for each reach due to efficiency improvements. Although
the reductions in diversions were assigned to a reach based on the distribution of irrigated
acres, in some cases the reductions would occur further upstream depending on the
location of the mainstem headgate. The amount delivered on-farm was based on the
average conveyance loss for each reach. Data on conveyance losses was based on
county-level information obtained from the USGS Water Use Data for 1995.

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