Regulatory Tools for Natural Resilience

Regulatory tools such as zoning codes and tree and stormwater ordinances are another way that cities can enhance natural resilience. In contrast to government operations and programs, these tools can be used to create requirements for how private land is used; several regulatory approaches that have been used to improve and target greening in frontline communities include zoning code amendments and overlays; tree ordinances; and stormwater ordinances.

Zoning Code Amendments and Overlays

Zoning codes establish standards for development and land use, and are written to implement local comprehensive plans (sometimes known as master plans or general plans).^{See footnote 1} Historically, zoning has been used as a tool to segregate communities of color in areas where environmental pollution is much more prevalent.^{See footnote 2} However, in recent years, some cities are using zoning amendments such as overlay districts to improve environmental justice outcomes; for example, zoning codes can be used to set landscape requirements for different land uses, and overlays can be used to create more stringent development requirements or environmental analysis requirements in frontline communities. Cities can work with communities to assess and remove zoning barriers to natural resilience. For example, cities are amending zoning codes that have historically acted as a barrier to urban agriculture by expanding the scope of agricultural and business activities permitted in residential zoning districts.^{See footnote 3}

Tree Ordinances

Many cities have enacted tree ordinances to regulate tree removal and implement goals for enhancing and preserving urban tree canopy. Tree ordinances typically set conditions for tree removal and requirements for replacement (or in-lieu fees) in the context of new development and other activity.^{See footnote 4} They may also create different replacement or mitigation requirements depending on whether the tree being removed is on private or city land, or in the streetscape.^{See footnote 5} Tree ordinances that create permitting fees or funds to collect in-lieu fees can establish a dedicated source of funding for tree planting efforts, which in some cities has been used to target areas with frontline communities, lower tree canopy, higher incidence of air pollution, and flooding challenges. Trees can also be considered a strategy for mitigating stormwater impacts and can be included in stormwater ordinances and regulations discussed below.

Stormwater Ordinances

Stormwater ordinances can be used to establish minimum water retention requirements (thereby encouraging the use of green infrastructure practices) or specify green infrastructure practices that new development or substantial renovations must employ.^{See footnote 6} Programs that utilize stormwater fees (which may be based on percentage or amount of impervious surface area) can encourage nature-based and green infrastructure by specifying reductions in fees, and revenue generated through fees can be utilized to fund capital improvements (including green infrastructure projects to mitigate stormwater runoff and pollution) and maintenance, including targeted stormwater mitigation efforts in flood prone areas.^{See footnote 7}

Cities should also consider the implications of new regulatory requirements for neighborhoods where low-income and other frontline communities are located to ensure that compliance is not overly burdensome. For example, stormwater utility fees as part of a regulatory program can help generate needed funding for green infrastructure improvements to manage stormwater, but compliance can be a burden for community-owned or -run properties if not exempted, such as community gardens.^{See footnote 8} Cities should also ensure in program design that the natural resilience benefits of regulatory programs reach frontline communities. Regulatory programs that establish funds for green infrastructure may be directed to low-greenspace areas consistent with planning; for example, tree ordinances creating permitting requirements for tree removal might provide an in-lieu fee alternative to direct tree replacement, and such fees can fund targeted tree planting in neighborhoods lacking tree canopy that may be more challenged by poor air quality, stormwater flooding, or other issues that urban forestry can help mitigate.

Considerations of Regulatory Tools for Natural Resilience

Lessons Learned

• Build fee-based (e.g., stormwater fees) or partially fee-based (e.g., green infrastructure requirements with in-lieu fee options) programs to generate revenue for greening, and as feasible, use these funds generated to support targeted greening investments in frontline communities.
• Before utilizing regulatory tools, evaluate local authority and any limitations on authority to regulate certain activities, and design ordinances carefully to ensure that regulations are within the scope of local authority.