Pool-Based Fire Defense System

In response to the 2025 Southern California fires, I started thinking about potential swimming pool-based fire prevention options. I’m hoping others find some useful information from my project.

First, some disclaimers:

1. I have no training or formal education in anything presented in this project. It is solely based on research and what I thought made sense. There are many ways to accomplish my goal. This is just the one I landed on.
2. Obviously, safety of yourself and loved-ones is the priority. I see my system being implemented if there is significant fire risk at my house or an evacuation order of 60 minutes minimum.
3. Though I have gained much useful information from other Instructable projects, documenting DIY projects has never been my thing. This might be a one-and-done. And I didn’t set out on this project planning to publish it, and though I hope for feedback, this project was admittedly quick and rough.
4. My home does not have an ideal “defensible zone” for fire, and we’re making some improvements. That’s not the scope of this project, but I stumbled upon some great information from Fire Safe Marin and their YouTube channel.
5. There were numerous resources that contributed to my project, but the most helpful were two YT vids from Sculpture for a Small Planet w/ Greg Bailey.
6. Lastly, sorry in advance for creating a TL;DR scenario. My favorite Instructables really get into the weeds on a subject so I’m trying to emulate those.

Let’s get started…

My first hope was to tie in a fire hose system to my 1 HP Hayward pool pump. I still may try tapping into my pool loop just like this or this, but I want multiple hoses. Though there are more variables to consider than simply power, I would need a 14 HP pool pump equivalent to this 212 cc Predator gas one. Additionally, once the pool water level falls below the skimmer (a few inches), the pool pump would just suck air (unless, at the time, you install a bypass loop in the skimmer basin). BTW, I do have a generator, so powering the pool pump wouldn’t be an issue in an emergency.

My next concern was cost. Obviously if you weigh the cost of losing my home and possessions, cost shouldn’t be a factor. But when you weigh the chance of a catastrophic fire, being able to implement this system, and the system being effective, cost is absolutely a factor. I came across systems tasked for this type of work and they were thousands of dollars. If spending >$5k on a little piece of mind is no biggie, go for it. Walking by a $5k stack of stuff in my garage daily, wondering if I’ll ever need it would raise my BP a little.

I decided on a 50 foot hose to handle the pool side of my house, then a 100 foot to reach the other side. I also was intrigued by homes that were saved by tripod sprinklers, and was surprised that you can buy them off the shelf locally. I hit the jackpot with one of my local Home Depot’s getting rid of one brand at $10/ea. I also thought I should have >100 psi rating, but now I don’t think that is necessary. Mine are 120 psi. With these, you can set them up and evacuate.

One can go down a rabbit hole of thread standards, but here is what you need to know: PVC is NPT (which are tapered). Fire hoses and accessories come two ways: NPSH/NPT and NH/NST. I stayed clear of NH/NST per my research. You can connect NPSH/NPT females to NPT male. One source said you can’t connect the NPSH/NPT male to NPT female without a pricey adapter, but I didn’t try. So all my hoses and nozzles are NPSH/NPT.

Parts List (including tax and shipping). If no price is listed, I already had it.

1. Predator (Harbor Freight) 2” 212cc Gasoline Engine Semi-Trash Water Pump - $276 (on sale)
2. 2" PVC Male X Female 25 foot suction hose - $92. Harbor Freight’s was in-store only.
3. 1-½” Fire Hose Nozzle NPSH/NPT, 2 Pack - $19
4. 1-1/2" ID x 50 FT Single Jacket TPU Fire Hose with NPSH Brass Couplings - $126
5. 1-1/2" ID x 100 FT Jacket Fire Hose NPSH (IPT) Straight Pipe Fittings - $237
6. 2” hose barb x female and male brass fittings for strain-relief 5’ hose - $20
7. 6 - Tripod sprinklers - $10/ea on clearance (normally $50) = $65
8. 2”, 1-½”, and ¾” straight schedule 40 PVC pipe
9. ¾” plywood and paint
10. PVC manifold (see photo). All parts schedule 40 - $50
11. 3 - Garden hose Y-splitters $16/ea and I already had one = $32
12. Sta-bil fuel storage stabilizer
13. Oatey PVC primer and cement
14. Garden hoses
15. 1 gallon jug for quick water priming of pump
16. TOTAL: $917. You're probably about $1k if you had to purchase the things I already had.

I built one PVC manifold reducing the 2” input to three 1-½” out. I also made a second manifold to multiple ¾” garden hose outputs (male). This garden hose manifold screws on to any of my 1-½” outs. I have two 1-½” PVC caps in case I’m not using all of the outputs. If I were to do it over, I'd use 1" for the garden hose manifold instead of 3/4".

I built a plywood box to store and transport the hoses and manifolds. You need access to the top of the pump for fuel. I created a simple, quick way for the box to snap onto the top of the pump. From scrap plywood, I used wood glue and brad nails. I flipped the pump upside down, on top of the box base, then secured these ‘L’ pieces and straight blocking wood. If you’re going to invert the pump, do it quickly or do it BEFORE you’ve added oil, or you run the risk of flooding everything with oil. Don’t ask how I know.

I also built a little mobile base with little casters I had lying around. They're not beefy but it’s a fairly smooth, hard surface from my garage to pool-side. The pump isn’t crazy heavy except with the storage box. One could simply just buy a plastic bin to store everything in and buy a small furniture dolly. I also wanted the pump to be removable from the base. I read an instance where a pump had vibrated into a person’s pool. When I didn’t have anything attached to the pump outlet, the pump moved along my pool deck fairly quickly. But I was just lowering my pool water level. Normally you would of course be using the outlet.

I was very concerned about not having strain-relief between pump and PVC manifold in that tugging on heavy, water-filled hoses the interface could easily snap it. Once I found how heavy the 1-½” water-filled hoses were, I think the tugging chances are a little less concerning. But 25’ of the 2” inlet hose is more than I need, so I cut 5’ off with a utility knife and used barbed male and female fittings on the ends. The hose is rated at 65 PSI, which is above my reading of roughly 55 psi.

I added a little Sta-Bil fuel stabilizer and gasoline to the pump. I’m planning to run the pump dry for storage, but test once a year. Some people leave the fuel with the stabilizer. Technically the fuel is good for 2 years with the stabilizer.

50’ and 100’ fire hoses covers most of my property but not all of it. I don’t want to buy a 150’ hose, so I could chain the 50’ and 100’. The end nozzles work fine but I’m not thrilled with how hard it is to twist them open/close when under pressure. I love the idea of the lever-controlled nozzles like real firefighters use, but they’re crazy expensive. I sprayed some lithium grease into the nozzle joint and it seemed to make it a bit easier.

I placed 6 tripod sprinklers around my property and numbered them. I set the radii on each, but it’s super quick and easy to adjust on the fly. I took photos of each’s location and created and printed a quick water-resistant guide to keep with the system along with a property map. I’m hoping that in the case I need to implement this system, that there is at least 50 psi of municipal water pressure, because there are some hose bibs within 10’ of where I want the tripods, so it would be much quicker than running garden hoses all over.