Short answer

Integrate a suite of low-impact development techniques, such as rain gardens and permeable surfaces, into residential designs to reduce stormwater runoff volume and mitigate pollution.

Field: Resource Management
Source: JAWRA Journal of the American Water Resources Association (2009)
Method: Paired watershed study
Evidence: Strong effect

Implementing low-impact development (LID) strategies in residential areas can significantly decrease stormwater runoff volume and associated pollutant loads compared to traditional development. This resource management research insight is drawn from a 2009 study published in JAWRA Journal of the American Water Resources Association. Using Paired watershed study, researchers explored how this design variable affects real-world outcomes. The key design takeaway: Integrate a suite of low-impact development techniques, such as rain gardens and permeable surfaces, into residential designs to reduce stormwater runoff volume and mitigate pollution.

Study

Resource ManagementHigh ImpactStrong effect

Low Impact Development Reduces Stormwater Runoff Volume by 42%

Implementing low-impact development (LID) strategies in residential areas can significantly decrease stormwater runoff volume and associated pollutant loads compared to traditional development.

JAWRA Journal of the American Water Resources Association · 2009

Key Findings

01Postconstruction storm flow in the traditional watershed increased significantly (600x), leading to higher pollutant exports.
02Postconstruction storm flow in the LID watershed was reduced by 42%, with no change in peak discharge.
03LID watershed showed reduced exports for ammonia-nitrogen, total Kjeldahl nitrogen, lead, and zinc, but increased exports for total suspended solids and total phosphorus.

Application

Design takeaway

Integrate a suite of low-impact development techniques, such as rain gardens and permeable surfaces, into residential designs to reduce stormwater runoff volume and mitigate pollution.

How to apply

When designing new residential developments or retrofitting existing ones, incorporate features like rain gardens, bioswales, permeable pavements, and green roofs to manage stormwater on-site.

Project actions

01Consider how different LID features might affect various types of pollutants.
02Quantify the potential reduction in runoff volume for your design project.

Method & Evidence

AimTo compare the quality and quantity of residential stormwater runoff from traditional and low-impact development (LID) watersheds.

MethodPaired watershed study

ProcedureA traditional residential watershed and an LID watershed (incorporating features like grass swales, rain gardens, and pervious concrete) were monitored. Stormwater samples were collected weekly and monthly and analyzed for various pollutants (nitrogen compounds, phosphorus, suspended solids, and heavy metals). Runoff quantity was also measured.

ContextResidential stormwater management

Variables

IVDevelopment type (Traditional vs. Low Impact Development)

DVStormwater runoff quantity (flow volume, peak discharge) and quality (pollutant concentrations and exports)

CVWatershed characteristics (e.g., residential land use), monitoring period (pre- vs. post-construction)

Strengths & Limitations

Strengths

+Paired watershed study design allows for direct comparison.
+Comprehensive analysis of multiple pollutants and runoff quantity.

Limitations

The study noted increased TSS and TP in the LID watershed, indicating that not all LID solutions are perfect for every pollutant.

Reliability & validity

The paired watershed design enhances validity by controlling for many site-specific variables. Reliability would depend on consistent monitoring and analytical procedures over time.

Think critically

While LID reduced overall runoff, it increased certain pollutants. How can designers optimize LID strategies to address these specific pollutant increases?

Design Principles

"Design for decentralized stormwater management using integrated low-impact development techniques to minimize runoff volume and pollutant export."

This research highlights the environmental benefits of integrating LID practices into urban planning and design. By managing stormwater at its source, designers can mitigate the negative impacts of increased runoff and pollution, leading to healthier aquatic ecosystems and more resilient urban environments.

What This Means for Your Design

Using 'green' building methods for managing rainwater, like rain gardens and special pavements, can cut down the amount of dirty water flowing away from houses by almost half compared to old ways.

How to use in your project

1.Reference this study when justifying the use of LID techniques in your design project to manage water runoff.
2.Use the percentage reduction in runoff as a quantifiable benefit of your design.

Add to My Project

Quick Cite

Paragraph starter

This research demonstrates that Low Impact Development (LID) strategies, such as the integration of rain gardens and permeable surfaces, can lead to a significant reduction in stormwater runoff volume, with a 42% decrease observed in the LID watershed compared to traditional development. This highlights the effectiveness of source control for mitigating urban water pollution.

Source

JAWRA Journal of the American Water Resources Association

Stormwater Runoff Quality and Quantity From Traditional and Low Impact Development Watersheds<sup>1</sup>

journal · 2009

View source

Questions About This Research

What does the research say about low impact development reduces stormwater runoff volume by 42%?: Integrate a suite of low-impact development techniques, such as rain gardens and permeable surfaces, into residential designs to reduce stormwater runoff volume and mitigate pollution. Evidence: JAWRA Journal of the American Water Resources Association (2009).
Why does "Low Impact Development Reduces Stormwater Runoff Volume by 42%" matter for design?: This research highlights the environmental benefits of integrating LID practices into urban planning and design. By managing stormwater at its source, designers can mitigate the negative impacts of increased runoff and pollution, leading to healthier aquatic ecosystems and more resilient urban environments.
How can designers apply this research?: Integrate a suite of low-impact development techniques, such as rain gardens and permeable surfaces, into residential designs to reduce stormwater runoff volume and mitigate pollution.
What were the main findings?: Postconstruction storm flow in the traditional watershed increased significantly (600x), leading to higher pollutant exports.. Postconstruction storm flow in the LID watershed was reduced by 42%, with no change in peak discharge.. LID watershed showed reduced exports for ammonia-nitrogen, total Kjeldahl nitrogen, lead, and zinc, but increased exports for total suspended solids and total phosphorus.
What research method was used?: Paired watershed study.
How strong is the evidence?: Evidence strength is rated Strong effect, based on a 2009 journal from JAWRA Journal of the American Water Resources Association.
What should I do differently in my next project?: When designing new residential developments or retrofitting existing ones, incorporate features like rain gardens, bioswales, permeable pavements, and green roofs to manage stormwater on-site.
What are the limitations?: Increased exports of TSS and TP were observed in the LID watershed, suggesting that specific LID features may not be universally effective for all pollutants and require tailored application.