We're launching a new series of blog posts based on City Parks, Clean Water: Making Great Places Using Green Infrastructure, a new report by The Trust for Public Land's Center for City Park Excellence.

The first-ever report focused entirely on the realities of green infrastructure and parks, City Parks, Clean Water explores numerous water-smart parks—both successful and unsuccessful. Through detailed case studies and interviews with experts, the report explains how cities can integrate recreation and stormwater management by creating parks that treat runoff as a multiple-benefit asset.

Problems surrounding stormwater have been plaguing cities and their parks for decades, but have attracted growing national attention as officials grapple with Clean Water Act compliance mandates. Scores of cities have negotiated long-term control plans with state and federal regulators to reduce combined sewer overflows and stormwater runoff. The costs of these long-term plans are projected to top $100 billion in the coming decades.

Facing such an expensive mandate, city officials are looking for alternatives beyond the traditional "gray infrastructure" of pipes, concrete holding tanks, and expanded capacity at sewage treatment centers. In contrast, using parks as "green infrastructure" often creates synergies and cost savings in making double-use of public lands for stormwater management.

Using city parks to proactively manage stormwater is a revolutionary step, but also a step back in time. Parks have been capturing runoff from the beginning, often unintentionally through vegetation and porous soils, sometimes purposefully through such large-scale projects as Frederick Law Olmsted's 1885 redesign of Boston's Muddy River to deal with festering mudflats and flooding. And  parks already play a significant role in managing cities' stormwater, since they comprise 5 percent, 10 percent or even more of every city's land area; renovating existing parks  and creating new parks to incorporate green infrastructure can be a real win-win situation for cities.

The school playground at P.S. 111 in Manhattan provides important neighborhood greenspace while also absorbing at least 700,000 gallons of stormwater runoff each year.

Using parks as infrastructure is a time-honored tradition, but it also requires new technologies and new practices. In some cases it entails economic costs; in others it provides savings and the ability to share an expense between multiple agencies. Practitioners need to be realistic about what green infrastructure can accomplish, what it costs to create and maintain, and how it impacts other facets of park life. Green infrastructure is not a simple, one-size-fits-all solution but rather one that needs to be carefully designed, implemented, and maintained in order to protect the parks' resources and at the same time manage stormwater over the long term.

These are the opportunities and pitfalls we will explore in the coming weeks with excerpts from City Parks, Clean Water. The next post in this series will focus on the innovative green infrastructure at Atlanta's Historic Fourth Ward Park.