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Thursday, January 22, 2015

Poor Scoping Leaves Residual Space

It is encouraging to see New York City developing more sustainable stormwater management. Unfortunately, the recent bioswale constructed on Bronx Park East at Pelham Parkway earns a grade of "D" as an urban infrastructure project. Poorly scoping the project left residual spaces and diminished functionality, which will ultimately be more expensive and disruptive to address later.

The bioswale detains storm water that would otherwise increase combined sewer overflows
The hatched area to the right probably could have been unpaved as well

The hatched area at this end is also useless, leftover space
It should be an active space as a refuge island as part of the greenway connection

A "D" is a passing grade, after all, but it appropriately captures strong dissatisfaction with poor performance. I do want to clarify that it is the City of New York that is being graded, and not the individual agency staff who implemented the project. This has all the markings of a larger process problem, rather than a question of project delivery by a particular project manager.

There is a critical gap in the greenway between Pelham Parkway and Bronx Park at this location, which was not addressed as part of this capital construction. Instead of scoping the project to address all the needs at the site in a timely and cost-effective way, the bioswale was installed with an overly narrow focus on stormwater management. The stormwater component itself appears satisfactory enough, but there is no innovation in its design that would offset the lack of comprehensive planning and additional costs that will be required to finish the overall job later.

Because of the lack of coordination between the design of the street operations and the bioswale, it appears some of the leftover space was a missed opportunity for a larger bioswale. The hatched portion of pavement at the corner, which is geometrically unsuitable for parking spaces, looks like it could have been unpaved if it had been properly identified as non-roadway space.

There is a missing connection between the Pelham Parkway Greenway and the Bronx River Greenway

The good news is that a basic solution appears to be feasible as a follow-up job with only modest resources, rather than requiring major reconstruction.

The existing dimensions from the curb to the double yellow lines at the parking stalls (including the moving lane and parallel parking lane) is a little more than 29 feet. The parking stalls to the double yellow line measure a bit more than 21 feet deep, for a total width of 50 feet. The typical markings for a Class II bike lane require a total width of 42 feet to the edge of the parking lane, which would measure eight feet wide, so that is the same 50 feet that are available. 

This would be a modest and rather disappointing solution, however, since it would leave cyclists without any physical protection from vehicles on the roadway, as well as putting them in the path of motorists pulling in and out of the parking spaces. There may have been an opportunity to find a protected lane behind the parking spaces if it had been included in the scope of the bioswale project.

The opportunity for a protected lane does still exist. Eliminating the parallel parking spaces on the east side of the street could yield enough space for a realignment. This would have only a modest impact on parking in the area, since it would result in a reduction of just four spaces. Several spaces are already lost due to a fire hydrant in the middle of this block. Unfortunately, bringing these four spaces into play as an isolated discussion for the greenway alone creates a difficult confrontation with those interests in the neighborhood that want to preserve every last parking space. A potential loss of parking as part of the larger project with more benefits may have been more attractive and easier to advance. An alternative design that provided additional width for a protected greenway connection while creating the bioswales may have also been considered, had it been included in the scope.

There is no curb ramp to enter Bronx Park (the greenway is the path on the right side)
At this juncture, it would be necessary to return to the community with the options of losing parking or marking a substandard design. Either option will require expenses and disruptions that will be more costly and bothersome now as standalone work. A new curb ramp is needed for access to the greenway inside Bronx Park. Design, concrete delivery and installation, markings, and maintenance of traffic could all have been included in the original project with only incremental costs. Now, after delays and the likelihood of increased tension with the local community, we may eventually get a water downed result, later, and at greater cost. Hopefully future projects can be scoped more comprehensively to ensure better results while minimizing waste.

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