Mont. Code § 7-12-4241
Subject to the provisions of 7-12-4242, a city or town may create, establish, and maintain a supplemental revolving fund out of the net revenues of parking meters to secure prompt payment of principal of and interest on special improvement district bonds issued under the provisions of 7-12-4241 through 7-12-4258 for improvements undertaken pursuant to this part and part 41 for the following purposes: for paving, repaving, macadamizing, remacadamizing, surfacing, resurfacing, oiling, reoiling, graveling, regraveling, piling, repiling, capping, recapping, grading, or regrading one or more streets, alleys, avenues, or other public places or ways in said city or town and/or constructing therein curbs or gutters or for the opening or widening of any street, avenue, alley, or other public way.
§ 7-12-4241, MCA