Mill Creek stream bed from this point to the city of Walla Walla is 

 dry in siimmer. Springs and seepage Trtiich maintain a slight flow in 

 the stream coiirse through the city is also diverted below the toum, 

 often leaving the channel completely dry from there to the mouth. 



The domestic sewage of the city of Walla Walla is given pri- 

 mary treatment and discharged into the stream. 



At the time of survey there were a few steelhead trout in the 

 lower stream section, but none in the upper portion. It was reported 

 that Mill creek at one time supported extensive runs of these fish. 

 No Chinook salmon have been reported from the stream for many years* 



Mill creek is of little or no potential value to anadromous 

 fish, 



5H-(1). Blue Creek , 5H-(2). Henry Canyon Creek , 5H-(3). 

 Tiger Creek , and 5H-(U). Low Ridge Creek . — (April 22, 193 7 J Burrows 

 & Whiteleather . ) These are small intermittent tributaries of Mill 

 creek. None of the Mill creek tributaries is of value to anadromous 

 fish« 



5l« Little Walla Walla River . — and 



$J. Stone Creek .— (April 22, 1937j Burrows & Whiteleather.) 

 These are tributaries of the Walla INalla River entering in the vicinity 

 of Mission bridge. The little Walla Walla River is only about h miles 

 long and is used largely as a waste ditch for irrigation Yfater. It is 

 a mud bottom stream having no siiitable spawning areas, sind is of no 

 value to saln»n» 



All of the water of Stone creek is diverted for irrigation, 

 and it has no value to salmon. 



5K. Yellowfaawk Creek , — (June 21, 1935j Burrows.) Enters the 

 Walla Walla River about 3 miles above Mission bridge. The stream is 

 8 miles long and was completely surveyed. The greater part of the 

 flow is obtained by diversion from Mill creek, and at the time of 

 survey was estimated at 25 c,f .s» The stream has a relatively flat 

 gradient and a mud bottom in some places. However, suitable spawning 

 area was estimated at about 65,000 square yards, or approximately 

 70 percent of the stream bed. Pools are not numerous but the deep 

 channels provide adequate resting places for fish. 



There are twenty-nine \mscreened diversions, all relatively 

 small since the total quantity of water diverted by them is only 25 

 c.f.s. There are only seven dams in connection with these diversions, 

 three of which ai-e small, low structures passable without difficulty. 

 Considering the more important permanent dams in upstream order, the 

 first is the Whitney dam, U^- feet high. It has no fishway but is 

 easily passable at the spillway. The second is the Walla Walla mill 



36 



