GSI Design
Green stormwater infrastructure design is a process for making decisions about the type, materials, sizing, location, configuration, implementation, and maintenance of GSI to meet functional and aesthetic goals for stormwater management.
This process combines the expertise of landscape architects, engineers, planners, public health specialists, stormwater managers, horticulturalists, and community members.
Better GSI design has the potential to increase the infrastructure’s ability to mitigate flooding by capturing a portion of stormwater where it lands.
University students learn from a professional about permeable pavement options.
How can this website help with GSI design?
The Design Process section of this website presents steps for integrating native soils research into community GSI planning and design. Because communities vary in their soils knowledge, capacity, and previous experience engaging in GSI planning and design, this guide suggests steps to follow and questions to consider for communities to tailor the process to fit their needs.
The website Resources section is a living collection of GSI information and tools from the University of Illinois and others that can help with design and planning. These resources can be filtered by topic, design process stage, and media type (Resource Library)
What other GSI design resources are available?
State and local governments have developed design manuals to reflect locally-appropriate considerations, such as vegetation recommendations and regulatory compliance. For example, in the Chicago metropolitan region, the Metropolitan Water Reclamation District (MWRD) has design guidance for grey and green stormwater infrastructure that complies with the Watershed Management Ordinance and provides a calculator tool to estimate runoff, detention, and volume control. Delta Institute developed GSI design templates for new development and recommends particular types of GSI for available site opportunities.
In general, many design resources are available, ranging from the conceptual (preliminary design and planning ideas) to the technical (construction) level. These guides typically contain only a minimal treatment of the role of native soils in GSI design, whereas this guide prioritizes the use of native subsoils as a key factor in optimizing the size and siting of GSI, based on research by the University of Illinois.