Work on the dam, located on the Deschutes river, was carried out by Santa Paula, California firm Hayward Baker to ensure the dam meets current earthquake safety standards.
The work, costing around US$38.5M, included the installation of 850 jet grout columns for the strengthening of foundation material. Engineers also constructed rock and soil stability berms and a drainage system at the toe of the dam.
In other news, USBR has announced that it is inviting ideas for the development in 2004 of Klamath river basin water, upstream of California's Iron Gate dam, in order to fulfil the 2002 National Oceanic and Atmospheric Administration (NOAA) Fisheries Biological Opinion (BO) requirements for a water bank, with options including land idling, substitution of groundwater, storage and other techniques.
The development area is to include 92.5Mm3 of water, 72Mm3 of which came from the 2003 Water Bank programme.
Ideas are to be submitted on forms, available from the USBR website.