The US utility said it is looking for US$4.7M towards the total cost of the project, budgeted at US$23.6M.
Improved fisheries for the salmon would be incorporated into the plant design at the dam, where it has been discharging increased volumes of water since early last year into the North Fork of the Skokomish river, in Mason County.
Tacoma Power hopes to receive the funds from the federal Government under the American Recovery and Reinvestment Act. The Skokomish Tribal nation have backed the project.
At the beginning of this year the utility and tribal nation agreed to a claims settlement as part of the relicensing of the Cushman facilities. In addition to a cash payment and transfer of land, the Skokomish will receive a small share of output from an existing plant and there are required improvements in river flows and fisheries.