Washington Water Power Co. Friday asked Washington regulators to approve a 15.6 percent rate increase for residential users of natural gas.
Other customer classes face smaller hikes.
Senior Rate Analyst Don Falkner said a second filing is expected in August. That, and a companion filing in Idaho, will cover the higher prices the company has paid to its gas suppliers in the last year.
The Spokane utility’s last general rate hike was in August 1990. Since then, said Falkner, WWP’s natural gas customer base in Washington has jumped 50 percent, to 108,000.
The company has made substantial investments in its distribution system to keep pace with the expansion, he said.
If approved by the Washington Utilities and Transportation Commission, the general rate case would generate $7.9 million in additional revenue for the company.
The average homeowner’s monthly bill would increase $5.93.
The “tracker” filing Falkner said the company will file later this summer will bring the total hike to $7.77 per month.
In Idaho, where rates are structured differently, only a tracker increase will be filed. The average homeowner’s bill will go up $5.49 if the request is approved by the Idaho Public Utilities Commission.
WWP serves 45,000 Idaho customers.
Falkner said consideration of all the filings by both states will likely take several months.
Even if approved in full, he added, area rates will remain among the nation’s lowest.
The only Washington customers whose rates will not increase are major industrial companies who buy their own gas and pay only for transportation.
Falkner said no rate hikes are planned for areas served by WWP subsidiaries in the Lake Tahoe area of California, and in Oregon.