Water
Installing a durable, Least Toxic: Potable Water System & Native Plant Friendly Irrigation System
Summary of Top Lessons Learned
The residential irrigation industry is dominated by plastic, especially PVC, so creating a system that avoids petrochemicals and toxics and is built to last through fire is difficult. If you are willing to put in the time and some extra initial investment, however, it is certainly possible. Finding a skilled installer one of, if not the hardest parts.
Abundant water storage for emergencies, with enough to keep structures protected, is critical in fire prone zones. Having enough water to also protect landscaping is optimal, funds permitting. These measures are additional to regular fire-wise maintenance, such as clearing defensible space, regular weeding and light irrigation, etc.
Making sure mechanical equipment needed to pump water has access to electricity 24/7/365 in all conditions is key, and this means backup generation with fuel on hand and regular maintenance to ensure working condition in emergencies.
Restoring Potable Water
One reason we bought our property was the fresh water in the Western Malibu canyons. When we first moved back to the area years before, we fell in love with the superior taste of the well water and the feeling of chlorine-free showers and baths at the little farmhouse we rented in Encinal Canyon. Our property has the same type of water, which flows at 25 gallons per minute from the 300 foot deep well and gets stored in an abundant storage tank system. It’s so delicious that even a friend who was sure our well water couldn’t beat his favorite imported bottled brand chose ours in a blind taste test hands down.
The fire burned out the electrical lines to our well pump, as well as the PVC potable water pipes, and the mud flow that followed encased our water storage system in a few feet of mud. So quite a bit of work was needed to get our drinking water availability restored.
To get there and make sure we built back better, we replaced the old PVC pipe for drinking water with copper pipe, ensured we had more water storage than required in case of emergency, and added a circulation pump to our potable water storage that was no longer shaded by trees so more exposed to sun (and planted fire resistant, native toyon around it for eventual shade). We also added a sediment filter at the tank to protect the pipes and remove bits of sediment from our drinking water.
To help make sure we don’t lose power on our well pump again in future emergencies, we connected a dedicated dual fuel liquid propane/gasoline generator to it. We’d like that backup power generation to be fossil free, when technology and funds allow, but for now, this is the most fire resistant, viable option.
Installing Fire Suppression
We aim to meet and exceed code to ensure that the home we rebuild never burns again, and one of the key strategies is a strong fire suppression system. Building code requires a minimum of 10,000 gallons of water storage connected by four inch pipe to a hydrant, plus sprinklers in the house. In addition to this, we will have 2-3 times that much water storage and rain cannons equipped with automated sensors that can saturate the structures in the event of a wildfire and the likelihood of having to eventually cope again without the aid of the fire department. After a good deal of research, we decided to go with the Hotshot system developed by an engineer who lives near us and saved his and other homes in Woolsey with this system, which he has been perfecting since the fire made him and anyone paying attention a lot smarter. We like that we can see where his system worked in Woolsey, that his pricing is reasonable, and that he seems in it sincerely to serve, rather than exploit, people in harm’s way from fire. Our design also includes a dedicated pump and sturdy generator (the fire recommends a Honda for its durability) for this system to ensure adequate pressure. And of course, the irrigation system will help keep the landscape on the entire property lightly watered at all times, and will be coordinated with the fire suppression system to be sure adequate water is available for the structure protection when needed.
Installing Irrigation System
In June 2022, we began restoring our irrigation system to help keep the coastal sagebrush-chaparral-oak woodland landscape around us moist during excessive dryness, fire conditions, and new planting. The system we inherited when we purchased our property in 2011 was a jerry-rigged maze of pipes that as often as not led to nowhere, and after the fire was no longer operational.
For the sprinkler heads, taking guidance from California native plant experts at Las Pilitas and Greg Rubin, we decided to use mostly MP rotators on 18 inch risers to simulate gentle rain. We figured out down the line a combination of drip and gator bags for the young oak tree plantings, as well as for the edible garden and fruit trees.
Our aim was to install a system that would be:
good for native plants from our canyon and general region (and those that play well with them), which would make up the vast majority of our landscape
durable (in fire, with rodents, etc)
non-toxic
Choosing the pipe system was more challenging. By far the most common irrigation material available is PVC, which we committed to not using, due to toxicity concerns – e.g. reliance on asbestos and release of dioxins when burned, a significant risk on our wildland property. The other options were galvanized steel pipe and HDPE. Galvanized steel pipes used to dominate the industry, but became less popular a few decades ago because it is less convenient to install, requiring threading instead of gluing like PVC, and the threaded connections are prone to rust and failure if not done properly. HDPE like PVC is a petro-based plastic but can be made more durably (utility pipe is often made of HDPE) and with less toxicity. We figured the best way to make the decision would be to consult the expert irrigation contractors.
Finding an irrigation contractor during the post-wildfire and mid-pandemic time was very difficult. Finding one who was willing to install material other than PVC – or who even knew how to use other options – was next to impossible. Out of the 20 or 30 contractors contacted, a couple seemed willing to try, but faded away when it came time to move forward. Only a couple plumbers and agricultural specialists agreed wholeheartedly that PVC was an outdated material for our property, but they were not up to the task of installing a system on our 3 acres of complex canyon terrain.
Finally, one of the major regional agriculture irrigation companies recommended a big landscaping company that they thought would take us on, and they did. The salesman was great. He came out quickly to see us, assured us his company could do it, and was quick to give us a reasonable bid and three week estimated time frame for installation. We settled on above ground galvanized pipe as our best option, due to cost and availability compared to HDPE. We also had observed that old galvanized pipe on our property had not been damaged in the fire, whereas PVC piping had been.
We are still digging up burned PVC pieces.
We worked with an irrigation designer recommended by the contracting company who seemed sensitive to and supportive of our priorities. More than a year out, with quite a bit paid above the initial bid, and a whole lot of troubleshooting and tweaking, we have a mostly working system. It turns out, the contracting company was not really expert at galvanized steel pipe systems either, since like everyone else, they install almost exclusively PVC, although to their credit they were willing to try and hang in there. They also helped us source many of the native plants on our list at wholesale rates, which was a plus.
As of mid-September 2023, we are down to only a small amount of hand watering and expect a completely working system soon to sustain nearly 1000 young plants we’ve put in the ground over the past few months. Those that grew on their own after the fire are happy as well. You can read more details about our planting in the Landscape section.