The Maryland General Assembly passed Senate Bill 236, the Sustainable Growth and Agricultural Preservation Act of 2012 (i.e. the Septic Bill) during the 2012 legislative session. The goal of the legislation is as follows:
"To limit the disproportionate impacts of large subdivisions on septic systems on our farm and forest land, streams, rivers and Chesapeake and Coastal Bays."
The Septic Bill is implemented through the preparation and adoption of growth tier mapping by the individual jurisdictions including municipalities. Frederick County adopted a growth tier map in February 2013. It is not required that a jurisdiction adopt the growth tier mapping, though for those that don't it would prohibit that jurisdiction's ability to approve major subdivisions. The growth tiers are as follows:
Tier I - areas currently served by public sewerage systems
Tier II - areas planned to be served by public sewerage systems
Tier III - areas not planned to be served by public sewerage systems and would allow for major subdivisions on individual septic systems
Tier IV - areas planned for agricultural, resource protection, preservation, or conservation
Tier IV Exemption
Without a Tier IV exemption, major subdivisions on septic would not be permitted in Tier IV areas. This would affect properties zoned Agricultural (A) that are large enough (minimum of 75 acres) to have agricultural cluster rights that could allow for residential subdivisions greater than five (5) lots. The Tier IV area also includes properties zoned Resource Conservation, which with a minimum lot size of 10 acres, rarely are able to create major subdivisions.
The MDP granted a Tier IV exemption in May 2013, which will allow the county to continue to approve major subdivisions on septic in the Tier IV area. The primary standard for consideration of an exemption is whether the zoning applicable to the Tier IV area allows for a density of one (1) dwelling or fewer per 20 acres. If a local jurisdiction's zoning meets this standard then the state would conduct additional analysis on subdivision history, development regulations, and an assessment of the total build out potential of the Tier IV area before a decision is rendered on the exemption request. This analysis was conducted by the MDP and presented to the Maryland Sustainable Growth Commission on May 13, 2013. The analysis showed that the county's estimated overall density at build out, including properties zoned Agricultural and Resource Conservation, is one (1) dwelling per 20.3 acres.