Kathleen English, AIA, talks about bioswales the way others might talk about a nice deck or flagstone patio. For her, it is the must-have landscape feature. Long interested in sustainable design, English in recent years turned her professional focus toward the often-complex hydrology and water issues surrounding buildings. As a longtime Houstonian, she saw how the lack of water as well as its periodic overabundance affected the city and development in it. She wondered how design could accommodate rapid rainfalls and the city’s notorious flash flooding in a more effective way, while maybe hanging on to more of the precious resource in the process.
“Many architects striving to create green buildings place them on sites in very conventional ways,” argues English. “These early site design decisions lead to traditional drainage solutions and stormwater management. By the time the site design is set, it’s already too late to maximize LID principles” She has become an outspoken advocate for Low Impact Development (LID), in an environment firmly stacked against changing the status quo. “For LID to work, the site plan must address how water is moved through the site, and that involves collaboration between civil engineers, architects, and landscape architects, as well as attention to building codes and regulations,” she says. And although few seem to share her passion, English is convinced that things can, and will, change.
With few established processes in place, English turned the firm English & Associates’ parking lot in Houston’s historic Sixth Ward into a LID laboratory. She set a goal to accommodate four inches of rain in one hour without introducing any water into the storm drains. Installing a 15,000-gallon rainwater storage system under the parking lot paving, she integrated a pump and irrigation tubing on the surface. Water flows through gravel filters, engineered soils, and plant materials and is cleaned of contaminants. The project reduced the site’s need for city water to zero and earned recognition from the EPA as a national best practices case study for rainwater collection. It set English on a course to educate others — architects, civil engineers, municipalities — about the potential to manage stormwater through architecture.
English introduced several of her own research-based concepts into her work with Harris County on the Evelyn Meador Branch Library. The previous building had been flooded and completely destroyed by Hurricane Ike. “Here was an opportunity to ask, ‘What does resilience mean when we build in an ecosystem this close to the coast?’” she says. In response, the project included newly constructed wetlands — the dominant ecosystem of the area prior to human intervention —
rain gardens and bioswales, as well as more than 30,000 gallons of rainwater detention and nearly 75,000 gallons of rainwater retention. The site requires no additional water for irrigation, earned a LEED Gold certification, and is the first county-owned building to feature integrated stormwater management.
Next, English turned her sights to her own house. “I wanted to know how far we could push it, how much water we could store on a conventional residential site,” she recalled. She installed pervious cover and a rainwater collection tank under the driveway and a bioswale alongside. She tested a solar-powered pump system and new materials and assemblies. She examined how a lower-cost, graded filter soil/gravel mix can maintain higher water flow rates, and she is in the process of fabricating and installing a modular green wall (with her neighbor’s blessing). There was much DIY-ing of the labor, and English and her husband treated themselves to his-and-hers rainwater collection tanks — but, she noted, it turns out you can store a large amount of water on even a tight residential site.
Now English is working on how a community like hers — West University Place — could incentivize and implement this kind of project on a larger scale. For now, she is encountering the usual resistance from municipal clients more interested in a political solution that checks the requisite boxes than a meaningful one. She admits it requires a fundamental shift in thinking, but English is willing to keep up the fight.
“My goal is to continue to politely wave the LID banner,” she says, understanding that allowing natural systems to do what they do is harder to budget for and to predict. “But we need to get over that,” she adds.
Her success in Harris County has already begun to show a way forward. Through her involvement with the Houston Land and Water Sustainability Forum (HLWSF), English helped create Harris County’s first guidelines for LID. She secured funding for the nation’s first-of-its-kind LID design competition and helped HLWSF push for legislation that requires all new state-owned buildings over 10,000 sf in Texas to incorporate rainwater collection systems. Even with so many firsts to her name, English presses ahead, sharing her knowledge and, very often, answering questions no one has thought to ask.
Canan Yetmen is an Austin-based writer.
Originally published in the March/April 2015 issue of Texas Architect.