Rain Water Collection for Fire Suppression
Recent wildfires in Central Texas have destroyed lives and property and made us very aware that we live in wildfire territory. Our area is a battleground between the arid Western deserts and the humid gulf coastal plains and lately, the desert has been winning. Throughout Central Texas, drought conditions are now commonly considered normal. We are adapting in some ways by improving fire response strategies, using fire resistant construction materials, planting fire-wise landscaping, and reducing fuel loads through controlled burning. All of this will help; however our main concern in the Central Texas area is that we often do not have enough water to control and extinguish wildfires.
I have witnessed several times from my front porch on the Browning Ranch helicopters attempting to fill their water bags from the Pedernales River with no success. After abandoning that effort, the helicopters had to fly to Lake Travis twenty miles away to re-fill while the subdivision across the river from me continued to burn. This put a significant burden on the volunteer fire department to contain the fire until other helicopters could return with water. The Volunteer Fire Department tanker trucks were re-filling with water in Johnson City five miles away. The question then becomes, how will we in Central Texas find the water to put out the more frequently occurring wildfires with our often dry rivers and reservoirs?
Many landowners obtain their water for fire suppression from surface water impoundments, such as stock tanks and ponds. On the Browning Ranch, we have a perennially-flowing spring-fed creek with a road crossing which seems like an ideal water source to access with gas-powered pumps. However, we and the Johnson City VFD have had bad experiences with dirty water - defined as water containing plant material, sediment, mud, and or rocks. Pond water, stock tank water, and creek/river water are too “dirty” to run through fire suppression equipment and cause significant damage to the pumps and nozzles. When lives are at stake, it is imperative to have reliable equipment and clean water.
We often rely on one of our agricultural wells for fire suppression water. The well pump, however, requires electricity, and often during a wildfire either the power lines are turned off by the electric company or the poles are consumed by the fire. Either of these events would result in a loss of power, making the well an unreliable source of water. Our next possible solution would be to position a large water tank next to the well and set up a float mechanism that would automatically turn on the well pump when the water dropped below a certain level. Should the power go out, we would still have a full tank. While this method could certainly work, we are concerned that, since the well site is in the middle of a pasture, a tank next to it would itself be vulnerable to fire. We have realized that what we really need is a large water source located in a safe area along one of our main ranch roads that does not require electricity to fill the tank or to discharge the tank.
For the past seven years, we have captured rainwater for our domestic needs at two locations on the Browning Ranch. Our experience with this means of obtaining water has given us confidence that it is a reliable method as long as there is sufficient storage capacity. Should we ever experience a normal year of thirty inches of precipitation, 16,500 gallons of rainwater will fall on a 1000 square foot roof over the course of that year. We consider this water to be an important resource that should be collected and stored. Over the past ten years on the Browning Ranch, I have recorded years with fifty-two inches of rain and years with thirteen inches of rain. I have learned that it is just as common in Central Texas to go five months without rain as is it to get five months of rain in one week. For example, in 2010 Tropical Storm Hermine overflowed my 20,000 gallon system in a matter of hours. The lowest water level we have ever experienced still provided us with two months of our water needs.
Our solution to the need for clean fire suppression water was to convert an old barn, not in use, into a rainwater collection barn. This barn was constructed in the early 1940’s for hay storage.
In order to make it suitable for rainwater collection, some of the wood framing and support posts needed to be replaced. Since one of the support posts needed to be removed completely to provide room for the rainwater tank, additional supports were installed to distribute the weight of the roof.
With the barn now strengthened, we installed the gutters and prepared the site for the rainwater tank. We selected a combination of road base material and ½ inch crushed limestone for the tank foundation that will need to support 115,000 pounds of weight. This material was leveled and packed in place with a vibratory roller.
The loop drive for the Fire Department trucks was the next project and this needed to be in place in order to enable access for the tank delivery truck.
At fifteen and one-half feet wide, the delivery truck required a highway escort crew that had to travel an additional eighty-five miles to detour around highway construction projects.
We predicted that getting the tank into the barn would be the biggest challenge of the whole project. To our amazement, it was perhaps the easiest task, thanks to an impressive crane on the delivery truck and our multipurpose Bobcat skid steer loader.
The most physically-demanding stage of the project was to create a railroad-tie retaining wall. We locked the ties in place with twenty-four inch x ¾ inch metal stakes using a sledgehammer. Once completed, the original grade of the site was restored.
The entire system was plumbed with two inch, four inch, and six inch PVC. Acquiring these supplies, such as a four inch PVC ball valve, was quite a challenge and required several special orders.
The plumbing configuration on the right is where the tank is filled from the gutters and the emergency fill line from our nearby creek. Below these overhead lines is the discharge pipe that is exposed on the north side of the barn along the loop road.
Our 14,000 gallon water tank now sits under a 1,200 square foot roof that will yield around 660 gallons per one inch of rain. Once this tank is full, it can re-fill the entire Johnson City VFD fleet of fire trucks three times. Eventually, we will add more water tanks and could one day store over 40,000 gallons of water inside the old barn. Maintaining a fire-wise landscape around the rainwater barn, as we do around all structures, is a better strategy than locating the water tanks in an open pasture.
Gas-powered pumps will transfer the water from our tanks to their fire trucks. We will locate a helicopter dip tank in a large open field near the rainwater barn that can be filled either from the rainwater tanks or from a nearby creek.
Our motivation for doing this is to not only provide water for fire suppression on the Browning Ranch but also to provide a reliable source of clean fire-suppression water for the neighboring community. We will grant access to the Volunteer Fire Department whenever they need water for fire suppression. Furthermore, we hope that this project will encourage other landowners to make use of every drop of rain that falls on a rooftop. If landowners can utilize old buildings and produce a clean water source for fire suppression, time, money, well water, and most likely lives will be saved.
I have learned over the years that rainwater collection is an ideal method to meet individual residential water needs. If the desert keeps on winning, the need to incorporate rainwater collection for municipal water needs will increase sharply. Our example is just one of the many ways that landowners can help out our fire departments to meet their water needs.