MUDDY WATERS

Greenway plan sees some ‘daylight’

Long-term project could resurrect Tibbetts Brook — finally — near Van Cortlandt

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The city’s environmental agency and its parks department presented Community Board 8 in late May a preliminary design for the new Putnam Greenway and a plan to bring Tibbetts Brook back up to the surface after a century underground.

While the $133 million project has been decades in the making, last month’s presentation provided a first look at what the borough’s newest stretch of parkland may look like.   

Through a process known as “daylighting,” the city plans to resurface a large section of the brook, and have it travel from the southern tip of Hester and Piero’s Mill Pond, or Van Cortlandt Lake, all the way down to 230th Street.

Running alongside it will be a new greenway full of pedestrian paths, benches, overlooks and educational signage — a marked improvement to what’s now a stretch of vacant land just off the Major Deegan Expressway, known as the CSX corridor.

In order to daylight the stream, the city will also make some significant changes to the bottom section of Van Cortlandt Park. “We are incorporating pocket wetlands, viewing overlooks, and adding in some entrances to give more flexibility in how people enter the park and enter the pathway,” said Dahlia Thompson, an outside consultant who led part of the presentation.

Right now, one of the main ways to cut across the park is to take the path that goes under, what’s commonly referred to as, the blue bridge. Yet the new stream corridor will run directly through that pathway.

Since that route will no longer be available, the city is planning to build a bridge over the brook in the middle of the Van Cortlandt Park Golf Course parking lot, so that cyclists and pedestrians can still easily navigate across the park. The agency is also currently evaluating options to install a new access point to the trail at the southern end of the park at Van Cortlandt Park South.

In terms of aesthetics, the parks department has instructed its consultants to design any new features so as to resemble already existing structures within the park.

“The kind of design direction that we’re giving to (the consultants, Hazan and Sawyer) right now is for the portions of the project that are within the park to match as closely with other nearby existing details in the park,” said Mitchel Loring, a representative from the parks department. “The section that is south of the park in the CSX is to be more of our modern design set.”

In the CSX section of the greenway, the stream corridor will become much narrower, with some areas allowing for a width of only about 25 feet. Because of that, the agency will construct a cantilevered path that hangs over the stream.

The new greenway will eventually come to an end at Verveelen Place, just before West 230th Street.

Thompson, the consultant, said having an entrance on a quieter street like Verveelen Place, rather than at a more heavily trafficked street, is a matter of safety.

“At (West) 230th Street, just like at Van Cortlandt Park South, those are entrances onto the Deegan,” she said. “And we felt that those are going to be very unsafe locations to have people coming in and out on their bikes right next to the on-ramp and off-ramp of the Deegan.”

But the city isn’t pouring millions of dollars into this project just to give the borough a face lift. It’s ultimately about improving the quality of the city’s waterways and water systems.

Currently, millions of gallons of fresh water from the brook are routed each day to an underground sewer line that runs parallel to Broadway and eventually end up being treated at the wastewater plant on Wards Island. 

That will no longer be the case. Once the project is completed, the stream will no longer regularly mix with the sewage, but will flow directly into the Harlem River — as it did over a century ago before being shoved underground.

The benefits are manifold. First, by restoring the hydraulic connection between the brook and the Harlem River, the project will reduce millions of gallons of sewer overflow spilling into the city’s rivers.

This, in turn, will also alleviate the city’s wastewater treatment facilities, as the brook’s waters will no longer have to be filtered through the Ward Island treatment plant.

The second benefit is less obvious. Currently, when the city needs to discharge water from the Jerome Park Reservoir, say in anticipation of a larger storm, that water is released to the city’s sewer system.

Through this new project, the city will be able to divert some of that discharge to the new daylighted brook, rather than the sewer system.

“This is going to be a more sustainable way to handle that drawdown of the reservoir without adding additional flows into the wastewater treatment plant,” Thompson said. Once again, lightening the load of the city’s sewer systems.

And while the city has backed this project for quite some time now, there’s still a long way to go before any sort of groundbreaking. But things are moving along: On July 11, DEP and parks will present this preliminary design to the Public Design Commission for review.

Tibbetts Brook, Putnam greenway, Van Cortlandt Park, Dahlia Thompson, Mitchel Loring, Ward Island, Verveelen Place

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