Laserfiche WebLink
r <br /> Also, a nvo-stepped pool structure will be built at the downstream mouth of the <br /> � culvert to provide access at a greater range of tidal lr.vels than previously. The design <br /> � criteria will be to allow passage at tiJal levels down to +8 feet (MLL1V). At this tidal level <br /> we estimate, based on 1939 tides during the period October 1-December 1, that p:�ssage <br /> .,.. would be pc-sible about 30% of thc time. <br /> � Z) Alter Partial IIarriers to Tligration up to Tiukiltco Boulc�crd <br /> � Hand•work will be i�sed to restructure 8 small cascades and waterfalls in this reach <br /> to improve passage at a greater range of flows than presently. Most of these features are <br /> �. assoaated with a drop in elevation of 5 feet or less, Careful attention to increasing plunge- <br /> � pool depths and making drops more verticnl will improve passage dramaticall}�. In addition, <br /> annual inspections of the reach will be conducted to insure passage remains unimpeded. <br /> M <br /> �� 3) Provide Passage at Mukiltco Boulevard <br /> � Offset baffles will be bolted to the tloor of this box culvert to eliminate sheet-flow <br /> � conditions. Also, a single step or two•step jump-pool will be constructed at the downstream <br /> end of the culvert to improve a:.cess. Additional work will be required in armoring the <br /> �, banks immediately adjacent to the culvert and redirecting the flow of the creek away from <br /> � a clay slide. <br /> !? 4) Small•Scalc Habitnt Improvements from I,�00•6r00' <br /> � <br /> � Two or three partial barriers to migration will be altered to improve passage in this <br /> reach. Also, the spawning riffles within this reach will be disturbed using hand tools to <br /> }' loosen sediment. 'This task will be conducted during the summer to avoid impacts on fshes <br /> � that may be using the reach downstream of Mukilteo IIlvd. <br /> Improvement of spawning habitat is proposed not because the present habitat is <br /> � severely degraded, but because establishing a new run of fish will be difficult enough with <br /> the potential for overharvest affccting the numbcrs of returning adults. The spawning <br /> habitai enhancement a�ll improve survival to emergence and increase the potential <br /> � contribution of each returning spawner. <br /> ' S) Crcation of an Oven�intering Pond <br /> � The stream channel contains abundant woody debris and generally excellent physical <br /> " habitat conditions.. However, the channel is located in a narrow valley through much of its <br /> � length, which means that as flows increase during the winter there are few arcas of low <br /> water velocities except those associated with woody debris. The pond is proposed to provide <br /> additional low velociry habitat during the winter period but will likely be used during the <br /> � summer also. <br /> 11�e pond will be located near the right bank of the stream on a small tributary. <br /> � Year-round access to the pond will be provided by the tributary. This rype of pond has <br /> proved to be a very desirable enhancement feature for streams in other areas in western <br /> Washington for coho salmon and cu[throat trout, particularly ehe Olympic Peninsula. <br /> r <br /> � ..6 <br />