SIOUX FALLS, S.D. (KELO) — MidAmerican Energy is asking state regulators in South Dakota to approve a natural gas rate increase to support the investment of more than $100 million in its natural gas distribution system in the state.

If approved, the request filed Wednesday with the South Dakota Public Utilities Commission would be the first rate increase since the company’s last request in 2014. The proposed adjustment addresses the approximately $108 million in capital investment and operating expenses incurred to maintain and upgrade natural gas infrastructure used to serve customers since the last rate increase.

The request also includes funding for planned infrastructure and safety improvements over the next two years, which the company says will help serve a growing South Dakota customer base, relocate natural gas facilities to accommodate road work and help fund projects designed to enhance safety.

Overall, the company is requesting a 6.4% rate increase, which would increase revenue by approximately $7 million annually. The request would raise residential customer gas rates by an average of $4.16 per month or $49.87 per year.

MidAmerican serves approximately 104,000 natural gas customers in 30 southeastern South Dakota cities, including Sioux Falls, Yankton and Vermillion. The company maintains more than 1,500 miles of larger gas mains in the state and 1,300 miles of smaller gas service lines that connect directly to customers.