Maryland Senate Bill 236 Explained

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The Sustainable Growth and Agricultural Preservation Act of 2012 (SB 236) limiting the use of septic systems in Maryland was introduced by Governor Martin O’Malley and passed by the General Assembly in 2012 after two years of development.

According to the Maryland Department of Planning website, “The Sustainable Growth and Agricultural Preservation Act of 2012 limits the spread of septic systems on large-lot residential development to reduce the last unchecked major source of nitrogen pollution into Chesapeake Bay and other waterways.”

The definition of minor and major subdivisions is up to local communities, with most establishing the boundary at between four and seven lots. By the end of 2012, all communities must map the land in their jurisdictions and rank them in one of four tiers:

Tier I
Currently served by sewer. Onsite systems not allowed.

Tier II
Future growth areas planned for sewer. Septic systems are allowed for minor subdivisions, but they are considered temporary and only allowed until a public sewer system is available.

Tier III
Large-lot development and rural areas on septic, not planned for sewage services. This is the only tier that allows septic systems for major subdivisions (community sewerage systems, shared facilities, or individual onsite systems. Any shared facilities must be managed by a “controlling authority” that is a government entity). Permitting of such a subdivision requires a public hearing and analysis of environmental and economic impacts. Requires best available technology to reduce nitrogen.

Tier IV
Areas zoned for preservation and conservation; areas dominated by forest lands or other natural areas or with zoning covenants or other restrictions aimed at conserving agricultural land or natural resources. Septic systems not allowed, major subdivisions are prohibited.

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