From Roof to Roots: Harnessing Rooftop Runoff for Research and Irrigation

May 13, 2025 3:53 pm

From Roof to Roots: Harnessing Rooftop Runoff for Research and Irrigation

Capturing rainwater for testing, treatment, and sustainable reuse

Purpose

To demonstrate building-scale rainwater harvesting for non-potable use and evaluate treatment strategies that could enable broader commercial applications of fit-for-purpose water reuse in urban settings.

Description

At CSU Spur, precipitation collected from the Hydro building rooftop is stored in an outdoor metal tank and used to irrigate select areas of the Hydro Backyard. In these zones, underground monitoring equipment tracks flow rates and water quality to support research on sustainable irrigation practices in semi-arid urban environments. In parallel, the same roof runoff is brought into the Water TAP lab, where researchers test various treatment methods—such as membrane filtration, microbial processes, and UV disinfection—to evaluate how this water could be safely used for other fit-for-purpose applications.

Impact

This project demonstrates how harvested rainwater can support urban green infrastructure while advancing research on water reuse strategies. CSU partners with Denver Water to ensure that the volume of water collected from the roof is returned to the South Platte River, maintaining ecological balance and flow conditions.

Partners

This integrated rainwater reuse system highlights collaboration across research, infrastructure, and watershed stewardship:

Project Photo Gallery

Smart Filtration, Naturally: eco-WEIR™ Demonstration at Water TAP

May 13, 2025 3:41 pm

Smart Filtration, Naturally: eco-WEIR™ Demonstration at Water TAP

Blending nature-based solutions with smart controls for better water management

Purpose

To evaluate the performance of the eco-WEIR™ system as a smart, nature-based pretreatment technology for stormwater, enhancing pollutant removal and supporting environmental recharge through improved flow control and filtration.

Description

The eco-WEIR™ system—developed by Dr. Jennifer Cherrier of The City University of New York and patented by Waterway Ecologics—brings together green infrastructure and smart sensor technology to enhance stormwater treatment and reuse. Installed at Water TAP, this modular, vegetated sand filter includes a smart weir that actively manages water retention to improve pollutant removal and support water reuse. The system’s two-layer design promotes both aerobic and anaerobic treatment, enabling robust removal of nutrients and contaminants. At CSU Spur, it’s deployed in tandem with the Minus ultrafiltration system to study its effectiveness as a pretreatment stage for various water sources onsite.

Impact

By combining nature-based design with active flow control, eco-WEIR™ demonstrates how smart green infrastructure can improve water quality and support circular water strategies. Its modular form makes it adaptable to urban settings while offering a scalable, sustainable treatment option.

Partners

This demonstration project combines academic innovation with field application:

What’s in the Mix? Evaluating Media for Pollutant Removal in Nature-Based Water Systems

May 6, 2025 2:25 pm

What’s in the Mix? Evaluating Media for Pollutant Removal in Nature-Based Water Treatment

Building better biofilters by testing how engineered media perform in real-world systems to improve the reliability of nature-based water treatment

Purpose

To evaluate the long-term performance of natural and engineered media used in nature-based systems, focusing on their effectiveness in removing pollutants—including nutrients, metals, and PFAS—and supporting informed, sustainable decision-making for utilities and designers.

Description

Funded by the Water Research Foundation (WRF #5257), this project evaluates natural and engineered filter media to enhance the performance of Nature-Based Systems (NbS) for water quality treatment. Researchers are assessing how well various materials remove pollutants like nutrients, metals, and PFAS, while also weighing factors like cost, maintenance, longevity, and environmental risks. Testing is conducted at Water TAP using urban stormwater, recycled water, and graywater, along with pilot-scale bioretention test plots in the Hydro Backyard. The research includes both lab-scale and field-scale experiments, culminating in a practical guidance document for utilities.

Impact

The findings will help utilities select media that balance performance with affordability and sustainability. By simplifying media comparison and supporting more informed design decisions, this project will lead to more effective and resilient green infrastructure solutions across the country.

Partners

This utility-focused research is supported by collaborative expertise in water quality and sustainable design:

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Minus Ultrafiltration Membrane Pilot System

May 6, 2025 1:27 pm

Ultrafiltration Meets Innovation: Piloting the Minus System at Water TAP

Optimizing membrane performance with AI-driven controls

Purpose

To test the performance of ultrafiltration technology on diverse alternative water sources—including stormwater, graywater, rainwater, and industrial flows—while advancing AI and machine learning models for autonomous system control and optimized fit-for-purpose water reuse

Description

Developed by researchers at Georgia Institute of Technology, the Minus ultrafiltration (UF) membrane pilot system is housed inside a 20-foot container at Water TAP. Originally designed to produce potable water from spent filter backwash at drinking water plants, the system is now being tested using urban stormwater collected onsite. The pilot features five hollow-fiber membrane modules, automated control systems, and real-time monitoring equipment, all integrated with programmable logic controllers and online data access. Future testing will expand to include a variety of alternative water sources available at Water TAP—including graywater, rainwater, and industrial sources—allowing researchers to evaluate performance across a range of real-world conditions.

Impact

This project advances sustainable water reuse by exploring how membrane treatment can reliably purify diverse water sources with minimal energy or chemical input. AI-assisted control models aim to improve system performance while supporting future applications like irrigation, green infrastructure, and even edible crop production.

Partners

This collaborative pilot bridges academic innovation and field deployment:

Urban Stormwater Research Takes Root: Bioretention Experimental Test Plots

May 6, 2025 12:42 pm

Urban Stormwater Research Takes Root at CSU Spur: Water TAP's Bioretention Pilot Project

A real-world experiment in Denver is helping shape greener, cleaner stormwater solutions for Colorado communities

Purpose

To evaluate the performance of urban bioretention systems using real stormwater runoff, with the goal of optimizing green infrastructure design for Colorado’s semi-arid climate and demonstrating how stormwater can be used as a fit-for-purpose alternative to potable water for landscape irrigation.

Description

At CSU Spur campus, researchers are leading a four-year study to improve the design and performance of bioretention systems used in urban streetscapes. The project features custom-built test plots that mimic streetside planters found across the Denver metro area, complete with region-specific and experimental media mixtures, vegetation, and stormwater-fed irrigation systems. Using real stormwater runoff collected onsite, researchers are monitoring water quality, flow, and plant health to optimize how these systems function in Colorado’s semi-arid climate.

Impact

Findings will guide more effective, low-maintenance green infrastructure that improves urban water quality, reduces irrigation needs, and supports healthier streetscapes. The research delivers practical insights for planners and engineers seeking resilient, climate-adapted stormwater solutions.

Partners

This collaborative project brings together municipal agencies and CSU experts in water systems, horticulture, and landscape design: