At a meeting on June 12, Princeton Council voted unanimously in favor of an ordinance to better address the growing problem of stormwater runoff. This was welcome news to members of the Stony Brook-Millstone Watershed Association, the Princeton Environmental Commission, Sustainable Princeton, Friends of Princeton Open Space, and others concerned with the increasing threat of major storms and the rise in developments that turn the ground into hard surfaces that don’t absorb water.

But the ordinance is only the first phase of action that environmentalists say must be taken in order to tackle the issue. “The passing of Princeton’s stormwater ordinance is a significant step forward to begin addressing these stormwater challenges,” said Molly Jones, executive director of Sustainable Princeton, this week. “This ordinance addresses stormwater for new construction. The next step is to address redevelopment. Here in Princeton, much of our development is redevelopment rather than new. The next step could have an even more significant impact. But you’ve got to take it piece by piece.”

Jim Waltman, executive director of the Stony Brook-Millstone Watershed Association, expressed similar sentiments. “What Princeton has done is take a big step forward,” he said. “It puts them in the top ten percent of the state in addressing this problem, and in a more rigorous way than what the state requires. The next step is to try to start addressing the existing problem.”

The ordinance harmonizes stormwater regulations from the former Borough and Township. It redefines the definition of minor and major subdivisions, and creates a yearly $50 permit for inspections of any stormwater system within a major subdivision. For every 400 square feet, two gallons of storage must be provided in the form of dry wells, rain gardens, or similar systems.

A major source of water contamination is polluted stormwater runoff, which can be tainted by the pesticides and fertilizers spread on lawns, as well as gas and antifreeze that are spilled from cars. “Leaks from failing septic systems and broken sewer pipes, waste from pets, soap from washing cars, and road salt spreads on roads, driveways, and sidewalks add to the problem,” reads a release from the Watershed Association.

“Stormwater runoff is the number one cause of water pollution and flooding,” Mr. Waltman told Council during the public comment portion of last week’s meeting. “The leading issue is the issue of redevelopment. Princeton is a mature community where much of the impervious surface was laid down long before we knew it was a problem.”

Sophie Glovier of the Princeton Environmental Commission said this week that most people associate water pollution with factories and industrial sites. “But stormwater runoff is the number one contributor to pollution in our water,” she said. “Between 1995 and 2012, the amount of impervious surface in our watershed increased 30 percent. I am a big open space person, and I walk the trails all the time. You can really see the erosion in our stream banks. The ground just can’t absorb it all, and it gets funneled into our streams. The banks start eroding, and that causes big problems.”

Not everyone was happy with the ordinance. Architect Joshua Zinder said he considers himself an environmentalist, but believes “there are still conflicts, ambiguities, and missed opportunities within the ordinance as it stands now,” he told Council. The ordinance puts a financial burden on the homeowner, he continued, suggesting tax relief for those who install green roofs, rain gardens, or similar systems.

“This is another case of providing a blanket ordinance across our town which is made up of neighborhoods of different densities, scales, and impervious coverage,” Mr. Zinder concluded. “Witherspoon-Jackson is not the same as Riverside. This ordinance is all stick and no carrot. We should be progressive and incentivize sustainable strategies and provide opportunities for homeowners to improve their homes and our neighborhoods … and not punish taxpayers with undue restrictions for issues that we are unwilling to confront as a municipality.”

On October 18, a panel discussion will be held at Princeton Public Library to help homeowners understand and cope with the stormwater runoff issue. A local architect, a landscape architect, and a representative of the Watershed Association will be among those on the panel.

“It’s a real example of collaboration by the town’s staff, the Watershed, the Princeton Environmental Commission, and Sustainable Princeton,” said Ms. Glovier. “We’re really coming at this in a very coordinated way, which will help everybody.”