New stormwater regulations went into effect in Maryland on May 4 with last-minute revisions that grant developers more opportunities to make their projects exempt from the rules.

The regulations were passed in the 2007 Maryland Stormwater Act to reduce runoff at newly developed sites and at urban sites redeveloped for new use.

But debates raged as the Maryland Department of the Environment worked with local jurisdictions to finalize details and put the regulations into effect.

In the end, a legislative committee passed emergency regulations that lengthened the grandfather period for projects in the pipeline and clarified conditions for waivers.

The revised regulations make it possible for projects with a defined amount of preliminary approvals in place to become exempt from the new rules. These projects must have full approval by May 4, 2013, and complete construction by May 4, 2017. Local jurisdictions hold the power to approve or reject the waivers.

MDE spokesperson Dawn Stoltzfus said that the emergency regulations headed off a number of pieces of legislation that could have seriously weakened the Stormwater Act.

"This is not a blanket waiver for all development. It's a possible waiver for people meeting very specific guidelines," Stoltzfus said. "There were no substantive changes to the technical standards, or how much ESD [environmental site design] has to be used."

Originally, only projects with complete approval by May 4 could be exempt from the new rules. But developers argued that many projects with preliminary approval would lose a significant amount of time and money invested in the planning process.

The debate caused multiple splits in the opinions of legislators and environmentalists, and a good deal of drama in Annapolis.

Legislators introduced several bills that would have not only expanded the grandfather clause, but weakened the regulations. "One in particular wanted to put the deadline for implementation back 10 years," Stoltzfus said.

At the same time, a set of legislators, builders and representatives from the Chesapeake Bay Foundation and 1,000 Friends of Maryland crafted compromise language that could be passed by committee without a legislative battle.

Others rejected any weakening of the 2007 rules. Waterkeepers Chesapeake, a coalition of advocacy organizations, was among them, along with former elected officials including state Sen. Joseph Tydings, U.S. Rep. Wayne Gilchrest, and Gov. Harry Hughes.

The MDE estimates that 1,000-1,500 projects could receive waivers if local jurisdictions decide to grant them.

Patuxent Riverkeeper Fred Tutman questioned the estimate. Eight of the 24 jurisdictions surveyed for this information didn't respond, and he said one estimate for Prince George's County alone is several times higher. "The impact of these regulations has been deliberately deflated. We have been given incomplete information in order to minimize the appearance of its impact and pass the emergency regulations. I think the builders are high-fiving," he said.