California has a debilitating housing shortage that is driving up rents and home prices, fueling an increase in homelessness and handicapping efforts to attract and retain businesses. The state needs another 3.5 million homes by 2025 to meet population and market demands, according to one analysis. But where to build? Just look at the news in recent days and it’s clear that as much as the state needs more homes, there are fewer and fewer good places to put them.

This fall’s devastating wildfires have reopened the debate over whether it’s possible to build (or rebuild) safely in high-risk areas. More than 45 people have been killed and 15,000 structures damaged or destroyed by wildfires this year. Researchers warn that this may be a taste of what’s to come as global warming fuels larger and more frequent wildfires, and as new development creeps further into the wildland-urban interfaces where homes and offices abut foothills, forests or other open land.

New data analysis and mapping tools may soon make it possible to identify the most fire-prone terrain. Traditionally, state and local governments have required new homes in such areas to be built with fire-resistant materials and brush around those properties to be cleared. But it’s time to ask whether those steps go far enough. State or local government authorities have to consider restrictions on housing developments in areas prone to wildfires because the threat to residents and firefighters is too great.

Some land managers have suggested requiring local governments to cover the cost of responding to and rebuilding after wildfires — expenses usually covered by insurance, the state and the federal government. Others want developers and new residents who impinge upon wildlands to pay hefty fees for firefighting and recovery. Both options would rightly discourage and decrease the number of homes built on the urban fringe.


Where can people live?

But climate change is making other areas of the landscape riskier for housing too. A state report released earlier this year predicted that melting polar ice could raise oceanic water levels by 10 feet over the next 70 years, which would flood low-lying coastal communities. That could make thousands of existing homes and future developments uninhabitable — or require an unprecedented public investment to try to make those communities safe.

There is also flooding risk inland. A warming atmosphere is expected to bring more severe weather, with periods of drought followed by periods of intense rain. That, coupled with more rapidly melting snowpack, could cause more frequent flooding on the state’s rivers and overwhelm flood control systems. That could mean more of the extremes seen earlier this year, when heavy rains caused flooding throughout the state and nearly overwhelmed the poorly maintained Oroville Dam. Thousands of residents had to evacuate. Cities and counties need to weigh these risks before allowing new housing tracts on undeveloped floodplains.


Even building in developed urban areas can be problematic. State officials have warned that siting homes within 500 feet of freeways puts residents at significantly greater risk of asthma, heart disease, cancer and other health problems linked to car and truck pollution. But, as The Times recently reported, local governments continue to approve home construction close to freeways, often because that’s the only land available or affordable, and the state has used grant money for affordable housing to help pay for the developments. While anti-pollution design features and air filters can offer some protection for residents, there is no escaping the fact that building housing right next to busy freeways puts children at risk of lifelong ailments.

In short, California needs to vastly increase its supply of homes, but it is becoming ever more risky to build them in the wildland-urban interface, or in low-lying coastal areas, or on floodplains, or next to freeways. So where can people live?

As the options for developable land narrow, California will increasingly have to develop and redevelop in cites and in established residential neighborhoods. Cities have to grow inward — with more development on vacant or underused lots amid buildings, greater density and more housing closer to workplaces and transit hubs. That’s rarely easy. Land is more expensive in urban areas, and it’s often difficult to persuade residents and political leaders to make room in their communities for more homes. Simply staying the course, however, is not an option. The status quo leaves too many people in too much risk.

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