A variety of best management practices can ensure a project’s long-term success
By Carolyn Howard
Although often unseen by the general public, stormwater controls have a substantial impact on daily life. They can reduce flooding, protect the environment, and even save money. Increasingly, both public and private projects, especially those with infrastructure improvements, utilize a variety of stormwater best management practices to meet regulatory requirements. A creative, cost-effective stormwater design starts in the conceptual design phase by considering multiple stormwater controls that can ultimately yield a number of benefits and is collaborative by seeking input from all stakeholders, including owner, user, architect/engineer, and contractor.
Stormwater solutions should be tailored to a project’s specific location, use, and goals; often multiple stormwater controls are needed to comply with today’s complex regulatory requirements. Multiple controls compel the project team to incorporate stormwater planning earlier in the design process. By starting sooner, the controls can be better integrated into a design, which will save time and money.
One such example is evident in Virginia’s Blue Ridge Mountains. The Virginia Military Institute (VMI), the country’s oldest state-supported military college, wanted to build a state-of-the-art training facility to help fulfill VMI’s mission to prepare citizen-soldiers for a life of service and leadership. Topographic and geographic site constraints forced the project team to get creative with the facility’s design, including the stormwater best management practices. VMI recognized the potential of this project to address lingering infrastructure issues around the proposed facility’s site.
The greatest site limitation was the Town Branch Creek, which runs beneath the building and is prone to flooding. Addressing this issue with stormwater controls accomplished a number of objectives, including no impact to the current flood zone adjacent to the creek at VMI and in the surrounding community. Stormwater controls were tailored to the site’s conditions, geology, and ultimate use early in the design process. The project called for more than a dozen stormwater controls, including a vegetative roof, three bioretention ponds, permeable pavers, an underground cistern to collect runoff and reuse within the building, a rainwater harvesting system, an underground stormwater retention facility, and five manufactured BMPs.
Utilizing multiple stormwater controls also can be critical in securing needed environmental permits. When working on permit approvals, take a big-picture approach. This recommendation is especially true with public infrastructure projects.
Think beyond the project’s immediate boundaries to options on other land. The result often provides more watershed benefits and volume controls than at the project site. For example, if your project is in a remote area, consider installing the required control, such as a bioretention basin, on other public land within the same watershed, such as next to a parking lot or public facility. This move will likely provide more benefits through greater pollutant removal and volume reduction instead of addressing an undeveloped area. Not only does this holistic approach benefit the municipality, but by thinking beyond a project’s boundaries, you can still meet the requirements to secure necessary permits.
Collaboration is a third benefit. By taking an integrated approach with multiple stormwater controls, the project team must collaborate more consistently because this approach requires significant understanding of each control and how it will interact with the others.
Finally, multiple stormwater controls produce more creative solutions for handling site constraints and environmental implications. For example, when working on a project with steep topography, the team is more likely to consider outside-the-box ideas, such as a “stepped” bioretention basin design where water flows into multiple terraces before overflowing through the lower basins as runoff after it has been filtered.
Creative solutions also deliver cost savings. Depending on the specific facility or infrastructure needed, a rainwater harvesting control could both filter water runoff and recycle the rainwater for use in a cooling and grey water system. Yet another innovative approach with multiple stormwater controls is to use permeable pavers.
While not every project will require a dozen – or even half a dozen – stormwater solutions, more infrastructure projects should leverage multiple stormwater controls because this integrated approach to stormwater management has a proven record that produces many benefits and delivers superior results.
Carolyn Howard, PE is vice president and regional manager for site development and infrastructure in the Blacksburg, Virginia office of Draper Aden Associates. She works closely with other engineers, private institutions and organizations, and public agencies on stormwater controls and best practices. She can be reached at email@example.com.