We can’t design our way out of the wildfires

By Emily E. Schlickman and Brett Milligan and Stephen M. Wheeler 6 minutes Lily

Wildfires in the American West are getting worse larger, more frequent and more severe. While efforts are underway to create fire-friendly communities, it is important to realize that we cannot simply engineer our way out of wildfires – some communities will need to start planning for a retreat.

Paradise, California is an example. For decades, this community has worked to reduce dry grasses, brush and forest overgrowth in the surrounding wilderness that could burn. He built firewalls to prevent fires from spreading, and promoted defensive space around the houses.

But in 2018, these efforts were not enough. The campfire started from wind-damaged power lines, swept across the ravine and destroyed more than 18,800 structures. Eighty-five people died.

Across Western America, thousands of communities like heaven Are at risk. Many, if not most, lie at the interface between wilderness and urban areas, an area between undeveloped land and urban areas where wildfires and uncontrolled growth are common. From 1990 to 2010, new housing at the interface between nature and the urban in the continental United States increased by 41%.

Whether in the form of large planned communities or incremental, house-by-house construction, developers have placed new homes in dangerous areas.

The First Street Foundation has created a National Wildfire Model that assesses fire risk at the local level to help communities understand and prepare. The map reflects the likelihood of a wildfire occurring in an area in 2022. [Image: First Street Foundation Wildfire Model]

It’s been almost four years since the campfire, but the population of Paradise is now less than 30% of what it once was. This makes Paradise one of the first documented cases of voluntary retirement in the face of wildfire risk. And while the notion of wildfire setback is controversial, politically tense and not yet endorsed by the general public, as experts in urban planning and environmental design, we believe the need for setback will become increasingly inevitable. .

But retirement isn’t just about moving wholesale. Here are four forms of retreat used to keep people out of harm’s way.

Limit future development

At one end of the wildfire retreat spectrum are development-limiting policies that create higher standards for new construction. These could be employed in moderate risk areas or communities with little inclination to change.

An example is San Diego’s steep slope guidelines that limit construction in areas with a large grade change because wildfires burn faster uphill. In the guidelines, steep slopes have a gradient of at least 25% and a vertical rise of at least 50 feet. In most cases, new buildings cannot encroach on this area and must be located at least 30 feet from the hill.

Although development-limiting policies like this prevent new construction in some of the most dangerous conditions, they often cannot eliminate the risk of fire.

Policies restricting development may include stricter building standards. The illustration shows the difference between a house on a steep hill which is difficult to defend against fire and one farther down the slope. [Image: Emily Schlickman]

Stop new construction

Further down the spectrum are construction shutdown measures, which prevent new construction from managing growth in high-risk parts of the interface between nature and cities.

Both of these first two levels of action could be implemented using basic planning tools, starting with general plans and county and city zoning and subdivision ordinances. For example, Los Angeles County recently updated its general plan to limit new proliferation in areas at risk of forest fires. Urban growth limits could also be adopted locally, as many suburban communities north of San Francisco have done, or could be mandated by states, like Oregon did in 1973.

Halting construction and managing growth in high-risk parts of the interface between nature and urban areas is another fallback tool. [Image: Emily Schlickman]

To facilitate the process, states and the federal government could designate fire risk areassimilar to Federal Emergency Management Agency flood maps. California already designates areas with three levels of fire risk: moderate, high and very high.

They could also develop laws for zoning fire-prone landscapes, similar to the legislation that has helped limit new developments along the coasts, on wetlands and along seismic faults.

Local governments could be incentivized to adopt these frameworks through planning and technical assistance grants or preference for infrastructure funding. At the same time, states or federal agencies could withhold funding from local authorities that allow development in high-risk areas.

In some cases, state agents could turn to the courts halt county-approved projects to prevent loss of life and property and reduce the costs taxpayers may pay to maintain and protect at-risk properties

Three high profile projects in California’s wildlands-urban interface have been stopped in court because their environmental impact reports do not adequately address the increased wildfire risk the projects create. (Full disclosure: For a short time in 2018, one of us, Emily Schlickman, worked as a design consultant on one — an experience that inspired this article.)

Incentives to encourage people to move

In high-risk areas, the technique of “incentive relocation” could be tested to help people move away from wildfires through programs such as voluntary buyouts. Similar programs have been used after floods.

Local governments would work with FEMA to offer eligible homeowners the pre-disaster value of their home in exchange for not rebuilding. To date, this type of federally-backed buyout program has yet to be implemented for wildfire areas, but some vulnerable communities have developed their own.

The City of Paradise created a buyout program funded by nonprofit grants and donations. However, only 300 acres of patchwork plots have been acquiredsuggesting that stronger incentives and more funding may be needed.

Removing government-backed fire insurance schemes or introducing risk-based variable fire insurance rates could also encourage people to avoid high-risk areas.

Another potential tool is a “transferable development rights” framework. Under such a framework, developers wishing to build more intensively in low-risk town centers could purchase development rights from landowners in rural areas where fire-prone land is to be preserved or returned to the public. unbuilt state. Rural owners are thus compensated for the loss of use of their property. These frameworks were used for growth management purposes in Montgomery County, Marylandand in Massachusetts and Colorado.

Incentive relocation can be used in high-risk areas by subsidizing the movement of certain people out of the way of wildfires. The illustrations show what could look like before and after. [Image: Emily Schlickman]

Moving entire communities, wholesale

Vulnerable communities may want to move but may not want to leave their neighbors and friends. “Bulk relocation” involves managing the entire relocation of a vulnerable community.

Although this technique has yet to be implemented for areas prone to wildfires, there is a long history of its use. after catastrophic floods. One location where it is currently used is Jean Charles Island, Louisiana, which has lost 98% of its landmass since 1955 due to erosion and sea level rise. In 2016, the community received a federal grant to plan a retreat to higher ground, including the design of a new community center 40 miles to the north and uplands of the island.

This technique, however, has drawbacks – from the complicated logistics and support required to relocate an entire community, to the time required to develop a resettlement plan, to potentially overburdening existing communities with displaced people.

In areas at extreme risk, mass relocation could be one approach – managing the relocation of an entire vulnerable community to a safer area. [Image: Emily Schlickman]

Even with ideal landscape management, wildfire risk to communities will continue to increase and removal of the interface between nature and the urban will become increasingly necessary. The main question is whether this retreat will be planned, safe and fair, or delayed, forced and catastrophic.


Emily E. Schlickman is Assistant Professor of Landscape Architecture and Environmental Design at the University University of California, Davis; Brett Milligan is Associate Professor of Landscape Architecture and Environmental Design at the University of California, Davis; and Stephen M. Wheeler is a professor of urban design, planning and sustainability at the University of California, Davis.

This article is republished from The conversation under Creative Commons license. Read it original article.

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