Park Mystery: Tidal Gates? Climate Change?

The tide was high, higher than usual — so Stephanie FitzGerald set out to discover why.

FitzGerald and her husband, Frank Cochran, spend long hours with other volunteers cleaning and maintaining Edgewood Park. They noticed recently that water levels have been higher than usual, with more consistent flooding in areas like the Duck Pond.

When FitzGerald heard that two of the tide gates on the West River were broken, she took a drive to the West Haven border to see for herself.

The two damaged tide gates, which FitzGerald said broke sometime this summer, were originally installed in 1919 when the City of New Haven sought to control the mosquito population. 

She had attributed the rise at first to rainfall, but then noticed that water levels didn’t dissipate as they had in the past in days following the storm. The Duck Pond continued to flood daily in recent months; access to the park’s soccer field has been almost completely hampered.

City Engineer Giovanni Zinn is aware of the problem. He said his office is working with Connecticut’s Department of Energy and Environmental Protection to procure the proper permits in order to repair the tide gates. Since the tide gates themselves and not the surrounding structure are broken, Zinn added, it’s not an ​“extremely complicated” fix. He said his office should have more information on how it can proceed within the next few weeks.

“We want to get those fixed as soon as we can,” Zinn said. 

While the original structure was put in place in 1919, the City of New Haven installed three self-regulating tide gates in 2012. According to FitzGerald, the original gates only allowed water to flow out of the Sound and prevented any salt water from entering the river. The 2012 installation of the three self-regulating gates — which would allow salt water to flow in but close automatically during high tide — was part of an urban conservation project intended to restore a more natural fluctuation of salinity to the river and its ecosystem. 

Zinn stated that the gates likely account for only a small portion of the flooding in the parks, especially because water flow is still inhibited by the existing structure and by the remaining tide gates.

He pointed to another source of water: increased rainfall. 

Nicole Davis, watershed coordinator at Save the Sound, part of the West River Watershed Coalition, agreed with Zinn. She said New Haven has been seeing more frequent large rain events as a result of climate change. She cited Hurricane Ida and Tropical Storm Henri, as well as a more recent nor’easter, as examples. 

In an ideal system, Davis said, stormwater would filter into the earth as groundwater or make its way to rivers via overland flow. But since New Haven as an urban area is largely paved and relies on storm drains in the event of rain, most of that extra water goes right into the rivers in a ​“constricted system.”

“When you have water coming up a river from a tide right when your tides come in, you’ve got water moving inland .. So that water that’s coming down a river kind of bumps up against it — it has nowhere to go,” Davis said. ​“It’s these big puddles of water pushing together, which kind of flood out into the floodplain, which is what they’re seeing in Edgewood Park.”

FitzGerald added that the West River Watershed Coalition is currently working on ways to conserve Edgewood Park, including plans to remediate erosion via natural means. Meetings are scheduled this month and next month. 

Davis added that New Haven’s geographic location makes the effects of a changing climate all the more visible.

“Flooding and how water moves is really one of the biggest things we’re seeing,” Davis said. ​“New Haven is at the mouth of most of these rivers, so it has all the cumulative impacts of everything that’s happening upstream, kind of flushing downstream in these rivers. So not only do we have the local effects of more water, we also have the impacts of more water coming downstream.”