Rain Check: Rethinking Stormwater

When it rains, cities feel it immediately. Stormwater rushes off rooftops, streets, and parking lots, collecting oil, debris, and pollutants along the way. With thoughtful stormwater management, however, water can be treated as a resource rather than a problem, supporting healthier landscapes while easing the burden on infrastructure.

Choosing the right stormwater solution is rarely straightforward. Stormwater design is inherently contextual and cannot rely on a one-size-fits-all approach. Today’s designers have access to a wide spectrum of strategies, ranging from long-established practices to newer, highly engineered systems.

Selecting the best option begins with a deep understanding of site-specific conditions. Every project presents a unique combination of variables that influence system performance, from spatial constraints to soil characteristics and pollutant profiles. The challenge is not simply choosing a tool but identifying the approach that best aligns with site conditions, regulatory requirements, and long-term performance goals.

Breaking it Down

Traditional stormwater solutions remain foundational for a reason. Systems such as bioswales, detention ponds, and rain gardens are well understood, cost-effective, and capable of delivering reliable performance when space allows. As a result, they are often the first strategies considered during planning and budgeting.

At the same time, the increasing demands of urban development have driven the evolution of alternative systems that offer greater flexibility. These newer or less conventional approaches are often designed to perform multiple functions within a compact footprint, allowing designers to meet both flow control and water quality goals without sacrificing valuable space. Examples include:

Aquabox: A modular system of subsurface detention units that can be customized to meet project-specific sizing needs. Ideal for use beneath parking lots and other paved areas, these underground “boxes” create a basin that captures stormwater and gradually releases it into the surrounding soil, or to a downstream storm system if infiltration is not feasible for the site.
Soil Cell Bioretention Systems: Included in upcoming 2026 updates to the Seattle Stormwater Code, these subsurface systems integrate seamlessly into dense urban environments. They capture and filter stormwater through engineered soil cells while also supporting healthy tree growth.
Underground Injection Control (UIC): An effective option for sites with suitable infiltration conditions, UIC systems use subsurface wells to disperse stormwater into the ground. They can reduce or eliminate the need for detention and, in some cases, provide water quality treatment. Many jurisdictions also offer credits for incorporating infiltration as a low-impact development strategy.
Contech Jellyfish Filter: A proprietary, high-capacity treatment system that captures both large debris and fine particulates. It works by directing runoff into a vault, where it passes through a series of filters before being safely discharged back into the environment.

Alternative Solutions in Action: University of Washington, Haggett Hall

Haggett Hall is a 230,000 square-foot student housing building situated in the center of the University of Washington’s Seattle campus. It was determined during planning that an existing water quality vault located within the footprint of the new building needed to be replaced. The initial design proposed a like-for-like replacement, which came with significant upfront costs and ongoing maintenance demands.

Instead, the project team re-evaluated site conditions and explored alternative solutions, ultimately selecting a Contech Jellyfish Filter. This approach proved more efficient in both space and cost, resulting in over $200,000 in project savings, along with reduced long-term maintenance costs for the university.

The system provided the necessary capacity to match the performance of the original vault while improving treatment efficiency and simplifying maintenance. It proved to be a strong fit for both the site constraints and the project’s long-term operational goals.

Because the Jellyfish system was new to both the jurisdiction and the university, it required a more hands-on approval process. The team worked closely with local regulators, the manufacturer, and university stakeholders to ensure alignment on system performance and maintenance expectations.

Ultimately, selecting the right stormwater solution is about balancing constraints with opportunity. The most successful designs respond directly to site conditions while making strategic use of both traditional and innovative systems. Looking for creative solutions to your next project? Get in touch with one of our stormwater experts: Kyle, Bailey, or Kelley.