Stormwater regulations designed to strengthen protection for water resources and the environment — but likely to increase development costs for builders and property owners — are in the works.

“Although I completely agree it’s necessary, it’s going to cause some hardship for some people. It’s not an inexpensive proposition,” said Joe Fossi.

A longtime Planning and Zoning Commission member, Fossi served on a subcommittee that spent two years developing the new regulations.

The commission voted unanimously on July 7 to send the proposed regulations to a public hearing on Sept. 1.

The new rules would govern the way storm runoff is handled — limited, captured, cleaned up, reduced and redirected — in development projects.

“The objective is stormwater quantity and quality — to control that,” Fossi said.

It’s an objective that seems increasingly necessary as weather patterns get more extreme.

“I think that we all agree that it does seem like we’re getting the 100-year storm more often than we used to, and same with 50-year and 30-year storms,” Fossi said.

“Although it’s going to be expensive for people,” Commissioner George Hanlon said, “the idea is the right idea and we’re doing the right thing for the town.”

Fossi told the commission he would have discussions with some local engineers to get a better idea of the costs people are likely to run into in trying to meet the proposed regulations. When the regulation gets to public hearing, he said he’d hope to be able to provide a range for what meeting the new rules would cost in most cases.

The proposed new rules focus on residential zones.

In commercial zones, applications go through the commission’s extensive “special permit process,” which requires a public hearing that usually involves a presentation by an engineer — addressing stormwater management, among other issues.

“The proposed stormwater reg applies specifically to residential zones,” said town Wetlands Agent Beth Peyser, who chaired the subcommittee. “It was determined that all proposed activities in commercial zones would trigger a special permit requirement and stormwater would be regulated under that special permit.”

Rescinded in 2016

The commission has tried before to regulate the handling of stormwater, but a regulation adopted in 2016 ran into objections from the public and was taken off the books a year later.

“We had one several years ago we rescinded because people didn’t believe it was fair,” Fossi said.

Regulation of stormwater by towns is encouraged but not required by the state.

Because planted areas absorb water but runoff is increased by development that adds more roof and paved surface areas — thus increasing “impervious coverage” — the state seeks to limit total development.

“Their concern is impervious coverage. When you exceed a certain impervious coverage, that’s when the problems start,” Fossi told the commission during its July 7 discussion.

“The state says any time a municipality gets 12 percent impervious coverage, there are detrimental effects,” he said.

A July 1 memo to the commission from its staff said state studies of streams in Connecticut supported the point:

“...No stream segment with over 12 percent impervious cover in its immediate upstream catchment met the state’s aquatic life criteria for a healthy stream,” th ememo said.

“As the amount of impervious cover exceeds 12 percent, unacceptable impacts to aquatic life can be predicted to occur in surface waters.”

The subcommittee put forward the regulations with the goal of limiting impervioius coverage.

“The object is to keep it below that 12 percent forever,” Fossi said. “I believe this document will do that.”

The regulations are designed to keep the peak flow of stormwater of properties being developed at the same level it was before the development project.

The regulation’s “purpose statement” puts it this way:

“The adoption of this regulation is intended to protect the public health and, safety, and welfare of Ridgefield’s residents, to avoid adverse and cumulative impacts to downstream properties and structures, and to protect the integrity of our wetlands and watercourses by regulating the development and redevelopment of properties in Ridgefield with the goal to maintain post-development peak rate of stormwater runoff (i.e., quantity of runoff) to a level that is less than or equal to pre-development conditions, and to manage quantity of runoff, and improve the water quality of the runoff.”

Downtown area

Ridgefield is mostly wooded residential areas governed by two- and three-acre zoning, and the highest levels of impervious coverage are in the commercial areas — Main Street, Danbury Road, Branchville.

“Clearly, the business district downtown has the most impervious coverage of any part of town,” Fossi said.

“If we were to hard and fast say you have to bring everything into conformance, chances are 90 percen- of the properties would never be able to do anything,” Fossi said.

And, the adoption of the regulations won’t make property owners rebuild existing properties to bring them into conformance.

“It’s clear that this is oriented toward new development — residential, commercial,” said commission member Charles Robbins. “It’s not intended to penalize any existing owner of property, to ask them to remediate their property to meet stormwater rules and regulations.

“Are there cases where the town or regulatory authority would demand an existing property, due to its effect on surrounding property, would make the changes?”

That would run against a basic principle of Connecticut zoning law, according to Planning and Zoning Director Richard Baldelli

“As soon as the commission adopts a regulation, that makes everything not in compliance with it legally non-comforming. State statutes strongly protect legal non-conformities,” Baldelli said. “I can’t think of an instance where you can impose a new regulation on an existing entity.”

Other towns?

During a roughly hour-long discussion of the regulations Fossi was asked if most other towns have stormwater regulations, while Ridgefield is without one.

“Certainly in Fairfield County, yes,” Fossi said. “Every town or almost every town in Fairfield County has one.”

Is there a state model regulation that all the towns base their local rules on?

“Every town seems to do it a little differently,” Fossi said.

Fossi said later that the town’s commitment to having open space helps it remains below the state’s 12 percent impervious coverage threshold.

“Our goal of 30 percent open space is what saves us,” he said. “Just in town and state toads the town is 5 percent impervious — that includes accessways, town roads and state roads. It’s 5 percent of the total area, paved. That’s a big number.”