Tetra Tech Green Infrastructure/Low Impact Development Code Review Checklist Tool
Tetra Tech’s Code Review Checklist Tool enables local governments to review their codes and ordinances to identify barriers to implementing green infrastructure (GI) and low impact development (LID) practices, and to make their codes more climate resilient. It provides a systematic checklist to identify:
- Existing policies and regulations that already encourage or support use of GI/LID
- Language and provisions that clearly limit or prevent the use of GI/LID
- Language that creates ambiguity that tends to discourage or prevent use of GI/LID
- Language or incentives that are now absent but that, if added, could better enable or encourage the use of GI/LID
This checklist evaluation considers a broad range of GI/LID techniques that can enhance climate resiliency such as downspout disconnection, rainwater harvesting, rain gardens, planter boxes, bioswales, permeable pavements, green streets, green parking design, green roofs, urban tree canopy, and preservation of open spaces.
This tool draws on more than a decade of Tetra Tech’s review of local codes for GI/LID opportunities and barriers as well as guidance documents such as the Integrating LID into Local Codes—A Guide for Local Governments, Puget Sound Partnership, 2011; Low Impact Development Model Ordinance Guidance Document, Urban Waters Resource Research Council and American Society of Civil Engineers, Draft 2013; and Better Site Design Handbook, Center for Watershed Protection, 1998. The checklist is organized by five key goals supporting GI/LID and has been used in a number of communities, most recently including San Diego, California; Macatawa, Michigan; Kenton County, Kentucky; San Antonio, Texas; Griffin, Georgia; Phoenix, Arizona; Durham, North Carolina; Sussex County, Delaware; and Raleigh, North Carolina.
Why Complete a GI/LID Code Review?
GI/LID enhances community resiliency by using natural features and processes to mitigate the impacts of climate change. GI/LID can be integral to climate resiliency by storing rainwater for groundwater reserves; harvesting rainwater on-site for irrigation or other uses; preserving areas in the city with high-infiltration soils; conserving areas around floodplains; using green infrastructure practices, such as bioretention areas, to reduce localized flooding and water quality impacts; and using trees and living roofs to lower building energy use and reduce the urban heat island effect.
Ordinances that bear on potential use of GI/LID in local jurisdictions typically are woven through the body of code, and barriers to using GI/LID often are embedded in those ordinances, sometimes in subtle ways. Barriers can take many forms. For example, ordinances sometimes treat vegetated GI/LID practices as being in addition to, rather than integrated with, requirements for open space, landscaping, setbacks, screening, trees, and other vegetation, which can unnecessarily make GI/LID an extra project cost. Other barriers can cause delays and add costs associated with variances, plan approvals, permits, and inspections.
Communities that want to become more climate resilient and convey the message that their jurisdictions welcome GI and LID as part of new development and redevelopment must ensure that ordinances and policies support and encourage use of GI/LID. Given the breadth of GI/LID practices, this means going beyond examining stormwater policies and standards to evaluating key provisions in the development ordinances that affect the feasibility, effectiveness, and cost of implementing GI/LID and preparing code language that can address GI/LID barriers.
The purpose of the code review is to propose clear and effective policies and standards that city council, county commissioners, staff, and the development community can support and use in implementing GI/LID and that can be considered in future code updates. This is a two-phased task. First, identify key GI/LID barriers. Second, recommend potential code revision language to address each barrier.
Neutral Facilitator is Important to Success
To be successful, the GI/LID code review must consider goals for development and redevelopment in that jurisdiction and the range of roles and functions of municipal or county operations. A neutral facilitator can work with the many local government departments and community stakeholders involved to review and discuss barriers identified; bring examples from other communities on how to address important barriers; and reach consensus on proposed GI/LID code changes to also address operational needs of different departments, development concerns, and potentially conflicting community goals. This upfront work gives a GI/LID program strong roots and keeps it growing.