You Can't Compress Water, But You Can Fit It Into a Smaller Hole!

Phillip Taylor, CPSWQ


On-site management of stormwater runoff volume is often one of the most challenging and expensive aspects of site stormwater design. Increased development and changes in development density, combined with more frequent and intense rainfall events, are resulting in significant flooding, with associated costs in the billions of dollars for damage. Many regulators are seeking to adjust design storms to higher volume scenarios, and combined with increasingly restrictive regulations limiting discharge rates, stormwater detention systems are becoming larger and harder to manage within the site design process.

Importantly, after decades of relying on detention system design, the frequency of flooding has not decreased and, in many places, is actually increasing. This necessitates adapting our thinking, modeling methods, and "go-to" practices to be more robust and resilient.

Traditional outlet control structures typically employ technology that has been used for thousands of years, including round orifice controls, rectangular weirs, and "V" notch weirs, each in various configurations to manage the outflow hydrograph. However, these traditional flow controls suffer from inflexibility. Designers can only control the flow using the outlet size and head pressure, unable to leverage water velocity or other available fluid dynamic properties to manipulate the outflow discharge curve. This limitation often results in detention systems being over or undersized or having excessively long drain down times depending on the final configuration.

While a fully automated, predictive computer-controlled outlet gate would represent the ideal outlet control solution, these systems are expensive, require power, necessitate regular inspection, and demand high levels of operator involvement. Additionally, security and reliability risks must be considered.

Fortunately, another option exists: the vortex flow control valve. Invented in the 1960s and extensively utilized in the wastewater industry, the vortex valve is still not widely known for its application in stormwater flow control. It offers numerous advantages over traditional controls, including:
• Customizable head discharge curves: This allows for more precise control over the outflow hydrograph.
• Larger outlets: These are less prone to blocking, reducing maintenance needs. • Optimized detention volume: This can lead to cost savings and increased climate resilience.
• Fully passive operation: No moving parts means minimal maintenance is required.

This presentation will introduce the vortex valve, explaining its operation, design, and integration with industry-standard software such as HydroCAD, HydroFlow, and other common hydraulic models. Case studies of successful projects will showcase how vortex flow control devices optimized inflow-outflow hydrograph relationships throughout the US, enabling designers to create more robust, often smaller detention systems while saving their clients significant money.

Learning Objectives

  • Analyze the limitations of traditional detention system design and understand the need for more robust and resilient solutions.
  • Evaluate the advantages and performance of vortex flow control valves as an alternative to traditional stormwater detention systems.
  • Apply vortex flow control technology in stormwater management projects using industry-standard software.

Presented by Phillip Taylor, CPSWQ | Technical Manager | Hydro International

Phillip Taylor, holds a New Zealand Certificate in Civil Engineering and is a US Certified Professional in Stormwater Quality and has dedicated his career to optimizing stormwater management. His diverse expertise spans private and public sectors across New Zealand, England, and the USA.

Phillip's journey began in soil and water conservation, laying the groundwork for his understanding of water resource management. He then transitioned to municipal engineering, honing his skills in water supply, wastewater treatment, and road projects. This breadth of experience instilled in him a holistic perspective on urban infrastructure and its impact on water quality.

As Hydro's Technical Manager, Phillip leverages his knowledge to spearhead three key areas:
-Job-Specific Solutions: He collaborates with clients to tailor stormwater management strategies for their unique needs and site constraints. -Education and Training: Phillip is passionate about empowering others. He develops comprehensive training programs and educational resources to equip engineers and practitioners with the latest knowledge and best practices. -Product Innovation: Driven by a keen interest in emerging technologies, Phillip champions the development and integration of cutting-edge solutions like bioretention cells and vortex flow control valves for more sustainable and efficient stormwater control.

Beyond professional pursuits, Phillip pushes his own boundaries. An avid adventure racer and cyclist, he constantly seeks new challenges and explores uncharted territories. This adventurous spirit fuels his relentless pursuit of innovative solutions and his dedication to shaping a future where clean water flows freely.