Taking a chance on the new normal

This year has been a difficult one in those parts of the country hit by wildfires. It seems as if we may need to expect more of the same to come. Governor Jerry Brown calls the deadly wildfires “the new normal.”

The consequences of a wildfire are often far-reaching and long-lasting. Of course, loss of life and injury — both human and animal — is the most heartbreaking immediate result, and the damage to people’s homes and businesses is also very disturbing. But apart from these immediate and direct consequences, there are other concerns — possibly less obvious but still serious — that arise as a result of these disasters.

It’s been a hot year. By August, there were no fewer that 83 wildfires across the U.S. More than 15,000 firefighters were busy trying to put them all out. In California alone, more than a million acres had burned.

In October, fires tore through Napa Valley in California, claiming the lives of 42 people and gutting almost 9,000 buildings. In December, fires have been sweeping through Southern California, exacerbated by high winds, causing extensive damage to an area of more than 2,000 square miles and making it necessary to evacuate almost 200,000 people from the area. 

According to the Orange County Register, more than 3.5 million homes in Southern California are situated in areas that Cal Fire has identified as hazard zones, ranging from moderate to very high. New homes built in designated fire hazard severity zones must be built according to the regulations laid out in Chapter 7A of the California building code, making homes fire-resistant. This helps protect new aboveground structures, but what about the drainage utility pipes?

Trouble beneath the surface

When fires of this magnitude hit built-up areas, the surface damage is significant, but there can also be problems underground. Most significantly, drainage pipes can be damaged, particularly if the pipe material used is high-density polyethylene (HDPE) or polypropylene (PP). During the recent Santa Rosa fires, underground drainage pipes either burned or melted. In one place, this lead to a sinkhole that was four feet wide and seven feet deep.  

Utility owners and municipalities in the affected areas are now faced with the job of inspecting all the pipes. In most cases, they’re forced to send video inspection equipment through the system to look for damage. This is time-consuming and costly. Until pipes are replaced, this is likely to become a recurring problem. The areas in question are still in fire zones and plastic remains vulnerable to heat.

In Santa Rosa, storm drain pipes in neighborhoods affected by the recent North Bay wildfire had to be inspected by engineers and geotech specialists. Municipal utility providers in the city were very concerned about the real risk of more sinkholes, landslides, and flooding that can occur as a result of the damage to storm-water pipes with the forthcoming rain.

Damage to underground drainage pipes resulting from the fires can also lead to serious problems later on. Soon, the rainy season will begin. Where drainage pipes have been melted or otherwise damaged by fire, we can expect an increase in flooding, mudslides, and possible sinkholes. Authorities are already warning those who live near recent burn sites to be aware of this increased risk. 

Sins of the fathers?

We’ve seen the use of HDPE / PP pipe in storm-drain systems increasing over the past thirty years. When these pipes were installed, the sticker price was often lower than for reinforced concrete pipe or corrugated metal pipe. Problems resulting from fire, deflection, joint failure, and flotation weren’t perhaps fully understood then.

When it comes to storm drains, city codes frequently stipulated that the last few yards be constructed of corrugated metal because of the risk of damage in case of fire. However, these city codes apparently didn’t take into account the risk of fire damage to pipes beyond that. Today, we’re living with the consequences of a sometimes decades-old lapse in foresight. Unfortunately, HDPE / PP pipe is still being installed in fire hazard zones today.

Scientists predict that the number of wildfires could double in the next thirty years. This increase is the result of a combination of climate change and development. Warmer temperatures and drought conditions create conditions that are perfect for fires. Development in recent years has also meant that we now fight small fires in areas that were previously allowed to burn. So today, there are vast areas of dry brush, which in the old days would have burnt off as a normal part of the natural lifecycle of forests. But now, we’ve built homes and other structures closer to these wildlands. For example, in just the sixty years from 1940 to 2000, the number of houses built within half a mile of a national forest more than quadrupled. We like living close to nature. The downside is that we now have homes located in close proximity to dangerous amounts of dry vegetation and brush.

Climate change and the fact that vegetation isn’t allowed to burn off as it’s done for thousands of years create the foundation of a recipe for powerful wildfires. For years, we’ve been developing areas that are closer to forests and wildlands. In many areas, it’s getting hotter and dryer. We can expect more fires that generate the kind of temperatures that can reach down to our underground pipe network. As Governor Brown says, we should probably accept this as “the new normal.”

I myself live in a part of California that’s been identified as an area with a severe hazard risk, so this is an issue very close to my heart. My house survived, but required evacuation from the Padua/Grand Prix fire in 2003. My family and I travel to the Napa Valley at least three times a year to enjoy the culinary delights and the winery tours.

I’m an engineer, but you don’t need a degree in civil engineering to understand that some materials burn and others don’t. You don’t need much more than simple common sense to appreciate that installing plastic drainage pipes in fire-prone areas is simply inviting trouble. HDPE and PP are plastic, and have a melting point of about 120-180 degrees centigrade. Reinforced concrete essentially does not melt. California building codes have addressed the matter of building new aboveground structures, it’s time to address the question of vulnerable underground drainage pipes by ending the practice of specifying plastic drainage pipes in these areas. 

Roll the dice?

Why specify a pipe that can possibly be damaged or destroyed by fire as part of a drainage system? By doing so, municipalities and utilities may be creating serious problems in the future. Isn’t it better to build right, right now? I think so, and it’s a philosophy that’s at the heart of our company culture today. To avoid finger-pointing in the future, I would encourage engineers and planners to take into account the growing greater prevalence in the future of wildfire heat.

Of course, there’s work to be done right now, finding the possible damage that’s already been done. At Thompson Pipe Group, we want to help if we can. Whether you’re a customer of ours or not, we’re happy to give you the benefit of our knowledge, experience, and technical support, simply because it’s the right thing to do.

Are serious wildfires going to be part of our built areas in the future? The risk seems to be growing. Let’s take this into account when we plan, build, or rehabilitate our underground infrastructure. By installing HDPE or PP plastic pipe in fire-prone areas — even by leaving existing HDPE or PP plastic pipe in place — some decision-makers are playing against the house, and the odds aren’t good. 

Branimir Kovac, Vice President, Thompson Pipe Group