My family and I live in a suburban county neighborhood outside my state’s capital city, and the school year recently restarted for my kids. This means early mornings, arguments over homework completion and plenty of “windshield time” when dropping off one of them seemingly daily. Too much windshield time can be dangerous, especially when it allows my brain to ruminate about what’s located right outside the glass. In the case of a road adjacent to my kid’s school, I often wonder whether utilization of more innovative stormwater management could’ve improved its overall function and appearance.
Streets, while critically important for transportation purposes, don’t need to solely exist to move vehicles—they can be constructed to meet multiple community and regulatory objectives. And since stormwater runoff is best treated at the source, why not turn the highly impervious right-of-way into a stormwater asset (if budget allows)? A thoughtfully designed street that optimizes stormwater treatment within the right-of-way can become an amenity that improves the overall neighborhood fabric without sacrificing water-quality or transportation goals.
The concept of “green streets” isn’t new. My first exposure to one was more than two decades ago in a locality where I cut my teeth in this industry.
The concept is simple: vegetation, soil and engineered media or structural system (e.g., bioretention, permeable pavers, proprietary biofiltration, etc.) are used to slow, filter and treat stormwater runoff from streets and sidewalks. Depending on the specific stormwater treatment practices selected, the environmental benefits can include improved water quality, reduced urban heat-island effects, better air quality and enhanced flood protection while also contributing to broader community benefits that may include reduced capital infrastructure costs, improved pedestrian safety and higher property values, among others. When installed properly, this strategy provides integrated stormwater management at the source while also creating numerous community co-benefits.
A Missed Opportunity
The subject of my current focus leads to the back entrance of the school, which dates to the 1920s and sits in the center of a historic 1800s mining village. As the county grew and the population sprawled, subdivisions sprang up, and much of the village character was lost. To quote Joni Mitchell, “they paved paradise and put up a parking lot.”
The area deserves a street befitting its history and local importance. Instead, this secondary roadway connecting two major thoroughfares, which was only built about five years ago and serves as the primary means of ingress and egress from a larger subdivision still actively under construction, feels like a sea of pavement with 40 feet of asphalt between the curbs and only a small strip of grass on each edge.
Between the students and residents, cut-through traffic, and construction vehicles, the road is busy; and (based on the most-recent aerial photography) the contributing drainage area supplies plenty of sediment, nutrients and trash to downstream waterways. When originally conceptualized and constructed, I’m sure the compliance strategy—using an offsite regional-extended detention pond for water quantity and quality—was consistent with state stormwater requirements. However, had a little more design creativity as well as regulatory and budget flexibility been deployed at the time, there’s no doubt the street could’ve come alive as a stormwater showpiece.
Imagine vegetated proprietary biofiltration planters lining the sidewalk to intercept runoff, planted curb bump outs with underground storage at key locations to provide runoff attenuation as well as slow traffic, a protected crosswalk with urban bioretention deployed to treat additional runoff and safely move pedestrians, and on-street parking supplied by permeable-paver street parking stalls that filter stormwater runoff where it falls. An added benefit of these innovative practices is that they take up less surface area, which preserves space for the primary function of the street and sidewalk.
It must be acknowledged, however, that street and sidewalk improvement projects—like other linear development projects—have their own unique challenges. Varying right-of-way widths, buried utilities, costly land acquisition or property disputes, and, especially in the case of public projects, budgets that require sacrifice and compromise are just a few of the challenges. I’m acquainted with enough design professionals to know the ones delivering this project likely did everything they could to balance all the varying stakeholder needs while trying to stay on time and within budget.
Creative Incentives for Improved Right-of-Way Development
If the intent is to create greener streets, then we must look at ways to incentivize such outcomes. Keep in mind, certain street types may be more suitable for this strategy than others. The following are a few examples of incentives that can be deployed to support broader utilization of green streets:
Propose or Update Existing Right-Of-Way Development Guidance
Development in the right-of-way frequently is governed by prescriptive public facility manuals (PFMs), which often dictate specific materials to be used as well as where and how they may be installed. If your community doesn’t have one, develop a PFM that permits a broad compliance toolbox which includes innovative stormwater infrastructure strategies. If one exists, review and update it to allow various types of proven terminal treatment solutions, including traditional green infrastructure practices such as bioretention and swales, but also proprietary biofiltration and filtration options because alternatives will be needed if infiltration isn’t desired within the roadway envelope.
Be sure to also consider guidance governing inlet design, media and vegetation selection, element location preferences (e.g., corner bump outs, mid-block planters, parking stall pervious pavers, etc.), and maintenance cycle expectations. Allowing optional underground storage elements in combination with treatment solutions (e.g., hybrid infrastructure) in the right-of-way adds flood protection and treatment within the available space.
Provide Grant Money
Backing up words with action is a great way to build community buy-in. Establishing a grant program to distribute money for various levels of projects could catalyze green street development. In the Chesapeake Bay Watershed, a successful example of such incentive can be found in the Green Streets, Green Jobs, Green Towns (G3) program run by the Chesapeake Bay Trust and funded by the U.S. Environmental Protection Agency, Chesapeake Bay Program and the West Virginia Department of Environmental Protection. This program provides money from conceptual planning through physical construction. Real change around green street design is happening in the watershed, in part, because of this program.
Build a Pilot Project
“New” can be scary. A municipal pilot project would provide proof of concept to the development community and citizens alike. Going through the process of developing a green street allows local staff to identify gaps or pain points in their review and/or construction processes and remedy them before private developers bear the brunt of those challenges. When complete, these act as excellent community demonstration projects. In the example near my kid’s school, imagine the outdoor experiential learning opportunities that could’ve happened.
Establish ‘Green Tape’ Permitting Procedures
Time is money in the development community. Creatively addressing a common complaint of lengthy permitting timetables by greenlighting greener right-of-way projects is a win-win for all stakeholders. Streamlined or expedited permitting is a great example of this method. Eligible projects may have their reviews shortened from multiple months to a few weeks. To establish eligibility, a locality generally creates pre-vetted design templates or standards. If a project checks all the boxes, then it moves up to the front of the queue.
Green streets are an amenity that improve water quality and enhance a community’s character. A sea of pavement can become an asset when regulatory flexibility and design creativity join forces to incentivize stormwater treatment within the right-of-way. Join me in working toward greater implementation of this compliance strategy across the country. In the meantime, I’ll just stare out my windshield at this street and wonder “what if” …