A small irrigation ditch takes off from the north bank I/3 mile 

 upstream, above a rock vring; dam. It now is reported to have been 

 screened. 



An irrigation ditch tekes off from the north bank I08 miles upstream 

 and above a 40 foot lonf: wing dam. It was diverting 1.7 c.f.s., and 

 was unprotected. 



An irrigation ditoh takes off from the south bank 2 l/2 miles 

 upstream, and was diverting 1 c.f.s. It has been screened. 



An irrigation pipe (30") to a ditch takes off from the north 

 bank 3.3 miles upstream, and was diverting 25 c.f.s. It has since 

 been reported as screened. 



An irrigation ditch takes off from the north channel 4 miles 

 upstream, above a lov/ rock diversion dam. It v/as diverting 1-2 

 c.f.s. and was not screened. 



An irrigation twitch tekes off from the north bank 5 l/2 miles 

 upstream and was diverting 3 c.f.s. It v/as not screened at the time 

 of inspection. 



The Tieton Irrigation Dam located 14 miles xipstream is built of 

 concrete and has a 2 to 4 foot spill. It is not a barrier at normal 

 water levels, but is a total block at lov/ water periods » No fishway 

 is provided. 



The Tieton Irrigation Ditch takes off at the dam, and has a 

 capacity of 320 c.f.s. It is also fed by diversions from Cowiche 

 Creek. An electric screen was installed in the ditch in 1929. The 

 Bureau of Fisheries later installed a battery of 4 drum type revolving 

 screens . 



The Mmrock Dam 22 miles upstream was completed in 1925, is 220 

 feet high (160 feet high from tunnel to spillway level), and is a total 

 barrier to fish. It has a spillway, but most of the water is discharged 

 through a tunnel 18 feet in diameter and having a capacity of 2,000 CofoS,, 

 which is located near the base of the dam. The drop over the spill or the 

 sudden pressure changes encountered in passing from the tunnel kills or 

 injures :aost fish coming out of the Tieton Reservoir. It is therefore 

 not practical to stock migratory fish above this dam. 



The Clear Creek Reservoir Dam was completed in 1918 and is located 

 1/4 mile above the backwater of Tieton Reservoir, on the TJorth Forkc The 

 dam is 53 feet high from the outlet pipe to the crest. 



4D-(2)a. Wildcat Creek 20 miles upstream is a good cold water feeder 

 stream, discharging 20-30 c.f.s., but is also steep and full of difficult 

 cascades. There is a small (1 or 2 c.f.s.) water supply intake 1 l/2 miles 

 upstream. No fish except native tout are reported. All tributaries to the 

 Tieton River rntering above the Rimrock Dam are nov/ inaccessible, and a 

 large portion of the former spawning arpa has been lost, including the North 

 and South Forks , each of which is 18 to 20 miles long. 



35 



