Natural gas supply in Idaho is adequate given increased demand-side management (DSM) programs, but some pipelines need to be expanded or upgraded within a few years, according to Intermountain Gas Co.

The MDU Resources Group utility’s updated integrated resource plan (IRP), submitted to the Idaho Public Utilities Commission (PUC), is subject to public comments through Jan. 12.

The utility is projecting faster growth in the customer base (2.69% annually) versus a recent average of 2.2%. However, no additional gas supplies are needed at this point.

“DSM, or programs aimed at managing the demand for natural gas rather than supply, is expected to play a role in helping the company meet demand and in lowering interstate transportation costs throughout the five-year planning period,” a PUC spokesperson said.

Stepped up DSM programs as outlined in the five-year IRP anticipate savings to grow to 374,292 therms in 2021 from 65,000 therms this year.

Intermountain also provided information on a liquefied natural gas (LNG) storage facility in Rexburg, ID, from which supplementary capacity would be available to meet peak-day demand in 2021. In addition, various industrial customers are equipped to switch off gas on peak-demand days and instead use diesel/fuel oil, coal, wood chips or propane.

Intermountain maintains four storage facilities that provide geographic and operational diversity, according to the PUC.

The IRP also envisions selective pipeline expansions and upgrades on the Intermountain distribution network, which is served by Rocky Mountain gas supply from Williams’ Northwest Pipeline Co. Intermountain maintains four major laterals on the Northwest system.

An upgrade to the intrastate State Street Lateral, a 16-mile link that moves gas from Caldwell to Boise, is planned. The IRP also calls for replacing a high-pressure pipeline in Canyon County, and to replace a pipeline that runs under the Snake River near Rexburg in eastern Idaho.