Maryland Code, Local Government § 21-606

(a)(1) Montgomery County may establish a stormwater management district that includes the land in its boundaries, except for the land in the City of Takoma Park.

(2) In its stormwater management district, Montgomery County shall provide efficient stormwater management services to the residents and property owners of the stormwater management district with adequate facilities for development and promotion of safety for life and property.

(3) The stormwater management services shall include those formerly performed by the Commission.

(4) Montgomery County may not exercise stormwater management authority in the City of Takoma Park unless the city and county otherwise agree.

(b)(1) The stormwater management district is a special taxing district for the purpose of stormwater management.

(2) Montgomery County may establish one or more special taxing areas within its stormwater management district.