As renowned fire scientist Jack Cohen has said repeatedly, the wildland fire problem is a home ignition problem, not a wildfire control problem. Cohen has been trying to help fire agencies understand this since 1999. Unfortunately, they have shown little interest. We are hoping with the recent wildfire tragedy in Paradise, California, attitudes will change.
But private citizens don’t have to wait.
There are a number of proven strategies and retrofits that can be implemented easily to homes and communities now. One is the installation of exterior fire sprinklers.
The story of the resistance to exterior fire sprinklers illuminates a crippling dichotomy between the structural fire protection and wildland fire communities. But first, the good news. Exterior fire sprinklers systems work, are affordable, and can be easily installed.
The Sprinklers Can Save Homes
The effectiveness of exterior fire sprinklers was proven during the 2007 wind-driven Ham Lake Fire in Cook County, Minnesota. In 2001, exterior sprinklers had been installed on 188 properties, including homes and a number of resorts. All 188 properties survived. More than 100 neighboring properties were destroyed.
The cost of the Cook County program was covered by a FEMA hazard mitigation grant. The program was finished on time and on budget by Wildfire Protection Systems (WPS), costing $764,255. Minnesota U.S. Senator Amy Klobuchar credited the program with saving over $42 million in property value. The grant paid 75% of the cost of the sprinklers. Individual property owners covered the balance. With a ready water source, a sprinkler system installation from WPS for an average home can cost between $10,000 to $15,000.
The sprinklers were so successful that a $3 million FEMA pre-disaster mitigation grant was awarded in 2008 to install additional wildfire sprinkler systems throughout Cook County. In 2013, another grant was awarded to install the systems in two additional counties, including properties with low-water resources. FEMA pre-disaster grants have also been used in Big Bear and Idyllwild, California to retrofit homes with non-flammable roofing and ember-resistant attic vents.
Canadians have successfully utilized exterior sprinklers too, with the implementation of portable sprinkler kits placed in the path of wildfires. The kits can tap into nearby water sources, pools, or local water tanks. These kits have protected over $2 billion in property value over the past 20 years in Canada, according to Morris Douglas, a retired advisor to various Ministries of Natural Resources.
Exterior sprinklers work by creating an environment that extinguishes embers (spotting firebrands) that are the primary cause of building ignition. The sprinklers do this by 1) hydrating potential fuels, thus making them less susceptible to ignition, 2) increasing humidity, and 3) creating a cooler microclimate around the home.
When we have suggested exterior fire sprinklers as an innovative way to protect homes from wildfires in California, we’ve typically encountered scoffs. The common reasons given for rejecting the idea:
– Too expensive (guesses as high as $60,000 have been mentioned).
– Wind will blow the water away from the house.
– Water pressure disappears during catastrophic fire events, disabling sprinklers.
– The power goes off during catastrophic events, disabling water pumps.
– People won’t have time to turn the sprinklers on.
All of these doubts are either incorrect or can be easily addressed.
Affordable. As mentioned above, grants can be obtained that can reduce the cost of a professionally installed system for an individual homeowner with a ready source of water to around $3,000. Without a grant, homeowners can install the systems themselves for considerably less than the professional price.
Wind. Yes, strong winds will deflect the water spray. However, despite 20-25 mph wind gusts during the Ham Lake Fire, the installed sprinkler systems worked well. Inspections during the fire found that although the rooftop sprinklers were the least effective when impacted by wind, other placements performed as expected. Some innovative solutions, such as WEEDS (see below) actually use wind to distribute the water.
Independent Systems. During a catastrophic fire event, critical infrastructure often collapses. Electrical power goes out and water pressure drops. This is why an exterior fire sprinkler system needs to be independent, or off the grid. A propane, gas, or diesel water pump (about $1,000) must be connected to a dependable water source (e.g. pool, 10,000 gallon water tank, or lake as is the case in Cook County). A 10,000 gal water tank costs about $6,000, so that adds to the system’s total price, but considering the cost of losing a home it’s a smart investment. A neighborhood could invest in a larger water tank that could serve a number of homes.
Time. When people are awakened in the middle of the night and see smoke everywhere, panic can set in. It’s difficult enough to evacuate, much less run outside and turn on the sprinklers. Unless the system is automated or can be activated by a switch on the way out (this adds to the cost), time is definitely an issue. However, it is not an excuse to dismiss the possibility of using exterior sprinklers.
Extra time can be found if communities can get their emergency alert systems up to speed, and trained CERT volunteers serve as support personnel (they do not evacuate). These fire volunteers can activate the systems, extinguish ember-caused spot fires, and help those who are stranded. During wind-driven, catastrophic wildfires there will never be enough professional emergency personnel available to do the job. Communities should consider picking up the slack.
Protecting their own Neighborhood
The effectiveness of expanding the ranks of emergency fire personnel with volunteers was demonstrated by Jeff and Cathy Moore in Chico during the Camp Fire. They stayed behind and were able to save their home and others around them. They doused surrounding vegetation and extinguished spot fires throughout their neighborhood. Their home also had exterior sprinklers. It definitely helped that they also had proper defensible space, but embers move right on through. In fact, open space just makes it easier for embers to reach the house.
Being a fire volunteer and staying behind when the evacuation call goes out is not a casual decision. Being confronted with the power, the noise, the smoke, and the swirling embers of a wildland fire can instill panic in the most seasoned wildland firefighter. This is why only those who are specially trained should stay behind to defend a community.
Many other residents have taken it upon themselves to retrofit their own homes with exterior sprinkler systems. Under-eave misters on the Conniry/Beasley home played a critical role in allowing the structure to survive the 2003 Cedar Fire in San Diego County. The home was located in a canyon where many homes and lives were lost to the flames. You can read their story here.
There are a number of other options becoming available as well. M-Bar Technologies offers an objective analysis of one approach that uses the wind to help distribute the water spray, the Wind-Enabled Ember Dousing System (WEEDS). The system is credited with saving another home threatened by the 2003 Cedar Fire.
Wildfire Protection Systems has begun installing exterior sprinkler systems in Payson, Arizona and Mill Valley, California.
Why so resistant?
Over the last few decades, two firefighting traditions have collided with the expansion of homes into the wildland urban interface (the WUI). The result has been a severe case of cognitive dissonance over how to deal with the fire threat.
Municipal fire departments were originally organized to deal with structural fires, but their primary job often becomes saving lives. This is one reason why interior fire sprinklers have become a required part of public buildings. Interior sprinklers have been life savers, for both firefighters and civilians, in burning structures – they provide the environment and the time needed for people to escape. They are not, however, generally designed to save structures, especially considering the damage caused by the water.
The primary goal of wildland firefighters, on the other hand, is to suppress wildfires fueled by vegetation.
As increasing numbers of developments have pushed into wildlands, creating the infamous wildland urban interface, the response of fire agencies has depended upon their particular traditions and experiences. Wildfire agencies like the U.S. Forest Service and Cal Fire see the problem as one of too much vegetation. Consequently, they push for additional habitat clearance operations, fuel breaks, and prescribed burns. Municipal fire departments have focused on improving building codes (e.g. non-flammable roofing, ember-resistant vents) and more recently, defensible space.
However, as the increasing number of fatalities and destroyed communities from wildfires demonstrates, these measures are proving inadequate. The issue is that the physics of ember movement and the actual cause of homes igniting (by embers) has yet to be fully integrated into how fire agencies approach the wildfire problem, or as Cohen says, the home ignition problem.
Ironically, even though it is becoming well known that embers ignite and ultimately lead to the destruction of communities a mile or more ahead of the fire front (despite defensible space, fuel breaks, and habitat clearance projects), wildfire agencies and politicians keep focusing on the big flames produced by wildland trees and shrubs. The old municipal/wildland firefighting paradigms have become blinding. The failure to see the real problem is an example of how cognitive dissonance can have disastrous consequences.
How can we keep embers at bay? Current firefighting paradigms need to be replaced with ones based on how the expanding wildland urban interface and a warming climate are changing the environment. Only then will the scoffing over exterior sprinklers end and public policy begin to properly address the home ignition problem.
For additional recommendations on how to improve the fire safety of your home and community, please see our page on Protecting Your Home. Also please see our full set of recommendations to policy makers on how to reduce wildfire losses in California.