<br />"
<br />r
<br />
<br />20
<br />
<br />DISTRIBUTION SYSTEM
<br />
<br />None. Released supplemental water would be carried in South
<br />Platte River to the diversion works of cooperating irrigation systems
<br />which are already in existence.
<br />
<br />PROJECT FEATURES
<br />
<br />NarrlYW8 Dam
<br />Located on South Platte River about 7 miles northwest of Fort
<br />Morgan, Colo.
<br />Type, rolled earthfill.
<br />Height above streambed 146 ft.
<br />Crest length 22,120 ft.
<br />Crest elevation 4,453 m.s.!.
<br />Volume of embankment 8,840,000 cu. yds.
<br />Spillway capacity (peak discharge) 27,600 c.f.s.
<br />1\Tarrows Reservoir
<br />Area top of joint-use pool, elevation 4,404.3, ] 4,963 acres.
<br />Shoreline top of joint-use pool, 40 miles.
<br />
<br />NARROWS RESERVOIR CAP,ACITY
<br />Ilnaere-reetj
<br />
<br />'''m
<br />
<br />Elevation
<br />(feet)
<br />
<br />Initial ~~d~~~ lOO-year1
<br />condlUons conditions
<br />0 0 0
<br />17,350 10,185 4,916
<br />32,810 27,nS 22,399
<br />313,025 355,227 335,870
<br />75,000 75,000 75,000
<br />475,000 475,000 475,000
<br />973,185 943,185 913,185
<br />575,373 575,373 575,373
<br />
<br />~~~~~~~~ ~ =::: ::::: :::::: :::::::::: :::::::::::::: i; ~g~
<br />~~~;~~auoi::~: :::::::::::::: ::: :::::::::: :::::::: :; ~~~
<br />Jojntuse__.h___.___._________.hhn______________ 4,404.3
<br />FfoodcontroL.___________h___.___.._______________ 4,428.5
<br />Sureba~:~.~~_a:~~~~~::::::::::::::::==:=:=::=:===------4;447---
<br />
<br />I For space illocaUon purposes, all sediment Is assumed to accumulate below the top of the conservatJOfl pool. Sedl-
<br />mentaccumuJation is estimated to be 60,000 acre-feet after 100 years oflJperatlon_
<br />
<br />HYDROLOGY
<br />
<br />Contributing drainage area above Narrows damsite, ]3,450 square
<br />miles.
<br />Annual runoff, average:
<br />Kersey, C610. (1947-61)____ _______________ 537,200 acre-feet
<br />Narrows damsite (estimated) _ _ _____ ___ ___ __ 365,200 acre-feet
<br />Annual runoff, maximum:
<br />Narrows damsite (estimated)___ _ _ ___ _____ _ __663,400 acre-feet
<br />Annual runoff, minimum:
<br />Narrows damsite (estimated)________________115, 700 acre-feet
<br />Peak daily discharge of record:
<br />Kersey, Colo_____________________31, 000 cubic feet per second
<br />Minimum daily discharge of record:
<br />Kersey, Colo_________________________28 cubic feet per second
<br />Inflow deSIgn flood:
<br />Volume, 20 days___"_____________------- 1,363,000 acre-feet
<br />Peak discharge_________________ 344,000 cubic feet per second
<br />Historical floods: 1844, 1864, 1867, 1876, ]894, 1921, 1933, 1935, and
<br />1965.
<br />
<br />21
<br />
<br />REMABKS
<br />The Narrows unit was authorized as a unit of the Missouri River
<br />Basin project by the Flood Control Acts of 1946 and 1950. Preconstruc-
<br />tion activities were initiated in 1947 but were su"bsequently terminated
<br />due to local opposition. Reauthorization of the unit became necessary
<br />with passage of Public Law 88-442, 88th Congress, H.R. 9521 on
<br />August ]4, 1964. .
<br />The Lower South Platte Water Conservancy District was formally
<br />organized on May 6, 1964. The district has indicated its willingness
<br />to contract for supplemental water to be made available by the unit.
<br />
<br />U.S, DEPARTMENT OF THE INTERIOR,
<br />BUREAU OF RECLAMATION,
<br />REGIONAL OFFICE, REGION 7,
<br />Denver, 0010., January 1967.
<br />
<br />To: Commissioner.
<br />From: Director.
<br />Subject: Feasibility report on the Narrows unit,
<br />Platte division, Missouri River Basin project,
<br />
<br />Colorado, South
<br />
<br />Part I-TRANSMITTAL
<br />
<br />PURPOSE
<br />
<br />This report is transmitted as the basis for securing congressional
<br />authorization of the potential Narrows unit as a unit of the compre-
<br />hensive Missouri River Basin project. As shown OI;l exhibit 1, the unit
<br />would be located in Weld, Morgan, Logan, Washington, and Sedgwick
<br />Counties in northeastern Colorado. The unit would serve the functions
<br />of irrigation, :flood control, recreation, and :fish and wildlife enhance-
<br />ment with incidental water quality improvement.
<br />
<br />AUTHORITY FOR REPORT
<br />
<br />This report is authorized by the Federal reclamation laws (act
<br />of June 17, ]902, 32 Stat. 388, and acts amendatory thereof or supple-
<br />mentary thereto).
<br />
<br />PLAN
<br />
<br />The unit will consist of the Narrows Dam and Reservoir, adjacent
<br />Jackson Lake which will be converted from irrigation to recreation-
<br />fish-wildlife use, and lands around both reservoirs for recreation and
<br />fish and wildlife developments. As provided in the Federal Water
<br />Project Recreation Act (Public Law 89-72) a non-Federal entity
<br />would administer appropriate water and land use for recreation
<br />purposes and repay reimbursable costs associated therewith.
<br />The Narrows Reservoir would have a total capacity of 973,185
<br />acre-feet at the top of the flood control pool. Of that capacity, 475,000
<br />acre-feet would be exclusively for flood control, 75,000 acre-feet would
<br />be joint flood control-irrigation capacity, 373,025 acre-feet would be
<br />for irrigation storage, and 50,160 acre-feet would be inactive and
<br />dead storege.
<br />The Narrows unit will provide salable project supplemental irriga-
<br />tion water averaging 119,400 acre-feet annually which would be applied
<br />
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