Chapter 1.2
Low-Impact Development and Stormwater Management

• ALL
• Remove Code Barriers
• Create Incentives
• Fill Regulatory Gaps

Mitigation of Lost Critical Habitats

INTRODUCTION

Even the most well designed, environmentally friendly developments may affect land in a way that damages or destroys important wildlife habitat. Nationally, the amount of habitable areas for wildlife is fast diminishing.[1] To ensure that new developments mitigate the loss of habitat that they damage or destroy, local governments are increasingly requiring developers to offset the loss of habitat in a variety of ways, for example, by purchasing equivalent habitat elsewhere or paying for off-site creation of new habitat.

An ordinance or local regulation requiring habitat mitigation should first require on-site preservation and enhancement of existing habitat. However, if on-site preservation is infeasible, offsetting the loss by enhancing wildlife habitat offsite is possible. For example, a local government may require a developer to purchase undeveloped land, enhance the wildlife habitat features, and protect the land with a conservation easement.[2]  Increasingly, local governments are establishing or supporting conservation land banks, entities that hold tracts of wildlife habitat and sell conservation credits to developers as a way to meet mitigation requirements.[3] The conservation bank can then use the proceeds from the sale of these credits to purchase additional conservation lands. Overall, the most effective local government mitigation programs will ensure that either there is no net loss of habitat area or, ideally, there is a net gain in habitat area. This requirement is important because replacement habitat can take years to mature to support the same amount of wildlife. Additionally, these ordinances may specify which types of habitat must be offset by mitigation, which zoning districts are subject to the requirements, and the ratio of affected habitat to preserved, replaced, or enhanced habitat.

EFFECTS

Loss of wildlife habitat has increased over the past decade, and has emerged as the number one cause of a reduction in global biodiversity.[4] Habitat preservation also  provides and helps support a range of ecological services such as water purification and management, pollution prevention and remediation, soil formation, food supply, diverse gene pools, recreation, and educational opportunities.[5] If local government does not require the offset of lost habitats, the cost of providing the services associated with the habitats often shifts to the government and taxpayers. By requiring offset of lost habitat, a local jurisdiction can secure the benefits of biodiversity for future generations.

Mitigation requirements may also help counter climate change. As urban development consumes more natural land, greenspace (land that is wholly or partially covered by vegetation) is destroyed in the process.[6] Vegetation found in greenspaces consumes carbon dioxide thereby reducing the amount of carbon dioxide in the atmosphere that causes the greenhouse effect.[7] Requiring developers to offset the loss of greenspace can help absorb greenhouse gases and mitigate climate change.

EXAMPLES

Snowmass Village, CO

The Town of Snowmass Village is located in the Rocky Mountains and is home to a steady population of elk, mule deer, and bighorn sheep. These species utilize the natural habitat in the municipality to live, reproduce, and survive the harsh mountain winters.[8] The Town protects critical habitat areas for these species with restrictive zoning provisions that minimize the potential impact of development on the wildlife habitat.[9]

Development within the habitat areas is generally prohibited, unless four out of the five city council members vote to consider such development.[10] If development is allowed to proceed, it must be designed so that large swaths of native vegetation are preserved, and any removed vegetation must be replaced.[11] However, if replacement is not possible, the developer must commit to on-site or off-site habitat enhancement.[12]

The Town’s Municipal Code defines enhancement as “the process of increasing wildlife carrying capacity on undisturbed habitat to replace the lost wildlife carrying capacity on habitats impacted, disturbed and/or destroyed by development.”[13] The Town sets forth aggressive enhancement requirements. For example, for every one acre of elk or mule deer winter range impacted, the developer must enhance eight acres; and for every acre of elk or bighorn sheep concentration habitat removed the developer must enhance five acres.[14] This results in a net gain of habitat area, promoting significant increases in long term wildlife habitat and biodiversity in the Town.

To view the provisions, see Snowmass Village, CO, Municipal Code § 16A-4-20 (f) (1) (d) (1998).

Camas, WA

The City of Camas is mostly residential, but surrounded by a significant amount of natural, undeveloped land. The City designates some of these areas as protected “habitat conservation areas” in which development is generally not allowed.[15] Developers who apply to use these lands must show that the activity will not substantially harm the habitat function or value, and is minimized to the greatest extent possible.[16] If the City finds that the activity would harm the habitat, the developer must take steps to mitigate that damage.[17] On site mitigation is preferred, although off site mitigation may be allowed in some cases.[18] If off-site mitigation is infeasible, the developer must pay a fee in lieu equal to the cost of implementing an off-site mitigation effort.[19]

Alternatively, the City uses habitat banking to allow developers to meet the requirements of the ordinance.[20] The City must approve all habitat banks prior to the issue of any mitigation credits.[21] Importantly, the habitat bank must be within the same watershed as the proposed development.[22] This ensures that the City does not lose the benefits of the habitat to another jurisdiction, and does not bear increased costs due to lost ecosystem services.

To view the provisions, see Camas, WA, Code of Ordinances § 16.61 (2008).

ADDITIONAL EXAMPLES

Los Angeles Cty., CA, Code of Ordinances § 22.44.1950 (2014) (prohibiting development in designated areas unless the developer offsets the impact to the habitat by permanently preserving a greater amount of land).

Indian River Cty., FL, Code of Ordinances § 928.06 (2) (1990) (requiring developers to replace destroyed wetlands at a ratio of two new wetlands for every one lost).

Pima Cty., AZ, Code of Ordinances §16.30.050 (2005) (requiring mitigation of loss of riparian habitat but allowing the developer an exemption from this requirement upon board approved contribution to a mitigation bank if on site mitigation is infeasible).

Lafourche Parish Council, LA, Code of Ordinances § 22-655 (2016) (detailing the requirements for setting up a habitat mitigation bank and requiring the bank to have financial surety of at least twenty or fifty years depending on the type of land preserved).

Dane Cty., WI, County Ordinances § 11.05 (current through 2017) (requiring submittal of mitigation plans for new developments in shore land and wetland areas).