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<br />17 Re~reatlon facilitios, consisting of picnic tables and
<br />shelters, camp~ng Un1 ts, water supply and sani tat ion faei I i ties, roads,
<br />trails, parking areas, hoat launching ramps, a heach_changehol.lse, a
<br />visitor center, and related facilities would be provided for bene_
<br />ficial use of the permanent pool and adjacent lands by the public.
<br />The recreation plan is presented in detail in Attachment Ill.
<br />
<br />the State of Colorado to maintain the permanent pool. It 1S assumed
<br />that the State would purchase the water required for the initial
<br />filling of the permanent pool.
<br />
<br />18, Construction of the project would require the purchase of
<br />7,140 acres of land in fee, of whiCh 5,460 acres would be for the dam
<br />and reservoir area, 1,350 acres for recreation, and 330 acres for re-
<br />location of the highway and railroad. Flowage easement on 150 acres
<br />located in the upper end of the reservoir also would be required.
<br />All land within the reservoir area up to five feet above the main
<br />spillway crest elevation would be acquired for the dam and reservoir.
<br />Recreation lands would consist of a strip of land around the reservoir,
<br />not less than 300 feet in width hori:ontally from the top of the
<br />spillway crest, supplemented by additional sites where visitor concen-
<br />trations would he expected to occur and where appropriate facilities
<br />would be developed, In acquiring the reservoir lands, it is proposed
<br />that the United States also would acquire the water rights associated
<br />with the lands_ The water rights would then be purchased by the State
<br />of Colorado at market value for maintenance of the permanent pool.
<br />
<br />21. The average annual flow of Fountain Creek. past Pueblo is
<br />38,370 acre-feet. Maintenance of a permanent pool in Fountain
<br />Reservoir with water rights to be acquired from reservoir lands would
<br />not reduce the annual flow of Fountain Creek at Pueblo. Furthermore,
<br />return flows from transmountain diversions of 47,000 acre-feet annually
<br />to the city of Colorado Springs probably will increase Fountain Creek
<br />flows. The capacity of the outlet conduit in Fountain Dam would be
<br />large enough to evacuate the flood control pool in a short time. The
<br />existing nondamaging channel capacity of the Arkansas River from Pueblo
<br />to Las Animas is about 5,000c.f.s. ThecondultforFountainllamwould
<br />be desi~ned to discharge water from the flood pool at a rate varying
<br />from 5,000 to 7,200 c.f.s. depending on the elevation of the water
<br />surface in the reservoir.
<br />
<br />19. Operation and maintenance of the project, with the exception
<br />of thc recreation development, would be the responsibility of the
<br />Federal Government. Non_Federalinterestswouldberequiredtooper.
<br />ate, maintain, and administer thc recreation, fish and wildlife facil-
<br />ities of the project. Federal responsibility would consist principally
<br />of maintaining the outlet works, gates, and slope protection on the dam
<br />embankment and spillway, A maintenance building would be provided for
<br />office space, shop space, and to house communication equipment. Livlng
<br />quarters would not be required as adequate housing is available nearby.
<br />Federal responsibility also would include stream gage observations and
<br />daily inspection of the dam and appurtenant works.
<br />
<br />22. The June 1965 flood on Fountain Creek was the largest of
<br />record, and it produced a volume of 39,660 acre_feet in a 3-day
<br />period. This flood storage could he evacuated from the reservoir in
<br />less than S days. With the recommended Arkansas River Channeli:ation
<br />project from Pueblo to Las Animas in operation, the flood control pool
<br />could be evacuated in less than 4 days. Historical data indicate that
<br />large magnitude floods requiring long detention periods occur infre-
<br />quently on Fountain Creek. During the period 1921-through 1969, three
<br />large floods occurred that would bave required detention of over a
<br />week. Since the largest of these, the 1965 flood, would require only
<br />about 8 days to drawdown under existing conditions, evaporation losses
<br />would be minor from the flood control pool in the proposed reservoir.
<br />
<br />20, EFFE;;:TS OF FOVNTI'.I1! .'IES!!:R'!D!R'ml rlq"UJW TO .'ORU !.JAR.TIN
<br />RSSERVVIR.- Water withdrawals would not be made for consumptive use
<br />from Fountain Reservoir in connection with any of the reco,wended
<br />purposes. The inviolate recreation pool would be maintained at
<br />20,000 acre_feet. Evaporation resulting from storage for recreation
<br />would depend upon the surface area of the pool. Initially,thearea
<br />of the recreation pool would be about 880 acres. The annual evapora-
<br />tion loss would be about 2,860 acre-feet and an average inflow to the
<br />reservoir of 4.0 c.f.s. would be required to offset the loss. At the
<br />end of 100 years the surface area of the 20,000 acre_foot pool would
<br />be about 970 acres, and an average inflow to the reservoir of 4.3 c.f.s.
<br />would be required to offset the loss due to evaporation. In the
<br />acquisition of the reservoir lands, it is proposed that the United
<br />States acquire the water rights of 13.6 c.f.s. which are assoc1ated
<br />withtheselllnds. These \O/ater rights would then be purcha.edby the
<br />
<br />23. Under existing conditions on the Arkansas River, floodwater
<br />detention losses from Fountain Reservoir would be more than offset by
<br />the reduced channel losses that would occur by confining flows to the
<br />normal low-flow channel. The June 1965 flood illustrated the magnitude
<br />of the losscs that occur frcm flocds ~oving down the Arkansas River
<br />valley. Flo\O/s originating fro~ Fountain and Chico Creeks were reduced
<br />from about 81,000 acre-feet at the Nepesta gage to about 71,000 aCre-
<br />feet at the Las ~nimas gage. Some of this water no doubt returned to
<br />the river, but little of it reached John Martin Reservoir. Most of
<br />these losses could have been prevented by upstream regulation of
<br />floodflo~.s.
<br />
<br />24. Do~.nstream water users are genuinely conccrned wlth upstream
<br />regulation and its effect on delivery of. water. It is generally be_
<br />lieved that upstream users would divert more from regulated flows than
<br />they would from unregulated flows. Historically, floods from Fountain
<br />Creek have been associated with large area storms that have covered
<br />most of the Arkansas River subbasin above John Martin Oam. Therefore,
<br />diversion \If flood releases frOJl1detention reservoirs prohahly would
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