Maryland Environment Secretary Robert   M. Summers

Maryland Environment Secretary Robert M. Summers said his department has drafted a policy requiring developers to offset the pollution impacts of their projects, in an effort to keep growth from undermining the Chesapeake Bay's cleanup. (Glenn Fawcett, 2009 / May 30, 2012)

Maryland officials are drawing up plans to require potentially costly water pollution "offsets" for new development to help clean up the Chesapeake Bay.

The new policy, which officials plan to begin airing next month, would force developers to pay for pollution reductions elsewhere to offset any increases in bay-fouling nitrogen that would result from their projects, said Robert M. Summers, state environment secretary.  He outlined the plan in Annapolis Tuesday in a "BayStat" meeting with Gov.Martin O'Malley and his staff.

Growth offsets are required under the bay "pollution diet" set by the Environmental Protection Agency, Summers said. A new state law aimed at limiting development on septic systems also mandates pollution offsets for any construction that would not be connected to a sewer system, he noted.

One way developers could offset the pollution predicted from their projects would be by paying farmers to plant more nitrogen-absorbing "cover crops,"  Summers said.

Under the offset policy, redevelopment projects would not have to compensate for their impacts, Summers said. Nor would new construction connected to a sewage treatment plant that's operating under its limit for discharging nitrogen to the bay.

All other building projects would have to offset 100 percent of the nitrogen that's projected to get into water ways from sewage plants or septic systems.  Higher density development hooked up to a state-of-the-art sewage plant would require a much smaller offset than would a subdivision built on large lots with septic systems.

Summers predicted that offsets could be costly because any pollution reductions made would have to go beyond what's required under EPA's bay diet.

"We've struggled to achieve (pollution) loading reductions" under the EPA plan, he explained, "so offsets  are going to be in short supply...We want to use them carefully."

Because greater offsets will be required for sprawling large-lot subdivisions on septic, the environment secretary said he expected the policy would discourage less compact development and spur "smart growth" in and around existing cities, towns and villages.

The offset policy relies on developers being able to pay to reduce pollution elsewhere.  Though some environmental advocates have expressed reservations about such pollution "trading," the Maryland environment secretary said it is "absolutely critical" to keeping growth from undermining the state's bay cleanup effort.  Trading also should spur jobs in environmental restoration, proponents say, while offering farmers a much-needed new source of revenue.

Summers said state officials plan to discuss the policy through the summer with builders, local officials and environmental leaders, with an eye to proposing regulations in December.