The following is an excerpt from City Parks, Clean Water, a report by the Trust for Public Land’s Center for City Park Excellence that examines the role of urban parks in managing stormwater. This is the fifteenth installment in a series of 20 posts.
Can a park be both a stormwater management unit and a recreation area? With proper negotiation, conversation, and careful planning, yes! However, it’s not common that goals easily jibe and that multiple benefits are received enthusiastically by every constituent. A rain garden can be beautiful, but if it replaces a soccer field, it might raise objections unless that sports venue is replaced. Philadelphia handles this problem with a Stormwater Plan Review Team, which brings together water department and parks department staff to evaluate green infrastructure projects for potential conflicts with park uses.
The city has not canceled any stormwater management projects because of recreation conflicts. However, Jessica Brooks, manager of the Green Stormwater Infrastructure program at the water department, says, “We’ve definitely moved them, made the surface portions smaller, or made them completely subsurface in order to allow for other uses to be maintained.” She notes, “We need to be very sensitive that we’re not taking out a space that is used for picnicking, sports, or other gatherings. This is often less obvious than you might think. It requires us to talk to the park users to really understand what they do and what they love.”
In the case of Cliveden Park in Philadelphia, the water department calculated that the park would be able to handle flow not only from within its own six acres but also from two city blocks uphill from the park. In theory, because of the topography, even more water could have been steered to Cliveden, but that would have transformed the park into a full-fledged detention pond, which was not something the neighborhood or the parks department wanted.
Cliveden Park had few amenities for a park its size – only a community building, a playground, a small garden, and walking paths. Thus, when the Philadelphia Water Department proposed constructing a series of stepped basins in the steeply sloping valley, with the last basin emptying into a rain garden, there was no outcry. The stormwater feature would not preempt any other uses. In storms the water burbles its way down the row of basins, pooling at the bottom in the garden. If the pond level reaches the height of an overflow outlet structure, it flows to the sewer. The result is a park only lightly impacted (or even improved) by extra water. In fact, as mitigation for the construction, the water department paid for an arching pedestrian bridge over the little valley, providing an attractive vista for users. Neighbors welcomed the addition, and the project was completed in less than 24 months.
“This project is in a high-impact location,” explained Brooks. “Our series of basins are very obvious to park users and even to passers-by on the street, so we were able to highlight it to the public. The grading is so ideal that it called out to us. It can handle a significant amount of water. We had good relationships with the community partners. And we didn’t have to do as much construction as we often have to — there were even already existing drainage structures at the bottom of the hill. It was a very successful project. It broke a lot of new ground for us,” she concluded. Fred Lewis, vice president of Friends of Cliveden Park, agreed. “We love it. We use it as a sort of outdoor classroom for kids, to explain the advantages of wetlands.”
In contrast, eight miles away at Columbus Square, things didn’t go quite as smoothly. The Philadelphia Water Department, after being invited by the park’s friends organization to consider the site for a stormwater project, was surprised by a hostile reception from the rest of the community. Because of neighborhood politics, everyone needed to be heard before things could proceed. Ultimately the negotiators compromised on constructing four sunken sidewalk planters (instead of six) and small, ornamental-but-not-functional “bookend” gardens at sidewalk grade to be under the control of neighborhood gardeners. Tellingly, after the project was completed, complaints and concerns evaporated; a few years later a second Columbus Square stormwater project was installed with no community objection.
It takes clear communication and community discussion for a park to successfully play a role as both a water management feature and a recreation area, but it is possible, as Philadelphia has demonstrated with its strong commitment to thorough research and attention to citizen wants.
Filed under: green infrastructure, maintenance/management, partnerships, planning Tagged: | Center for City Park Excellence, City Parks Clean Water, Cliveden Park, Columbus Square, green infrastructure, philadelphia, stormwater, stormwater management, Trust for Public Land, urban parks