 In 2009, Stanford University completed construction of a new fish screen and ladder as the previous fish ladder was an "Alaska Steep Pass" designed for much higher flows.The upper watershed is wholly protected within the Los Trancos Open Space Preserve just northwest of Page Mill Road and east of Skyline Boulevard.Spawning steelhead in Los Trancos Creek below the Felt Lake diversion dam vary from zero in drought years to several hundreds in wetter years and occurs from February to April.