Tapping into Fire hydrant

Does anyone here have experience tapping into a fire hydrant for water? I have a large project I’m in the middle of completing and the water pressure on the building is horrible. What do I need to do to get access for a hydrant? Where can I get the right hose attachment? Any advice would be helpful.

You need to get into contact with your local municipality to fill out some paperwork get a hydrant meter…Warning, deposits are not cheap on them…

Thanks Trey. The building I’m working on said they would pay for anything that needs to be covered, I just need to be shown what direction to go in and what to expect if I can tap into the hydrant.

Yep, you got that right! Also they’re not in a hurry to return your deposit either. Deposits range from free to $1500.00 depending on municipality and size of meter.

Most Industrial Plumbing Supply Companies have what you need or know who to send you to.

Hydrant wrench is #1, municipalities don’t allow pipe wrenches on hydrants. Are you going to “Quick Fill” your tank from the hydrant or run water hose from the hydrant to your tank?

If you’re quick filling you’ll need 25" of 2" fire hose. This will screw into the hydrant’s small port. If the meter does not have a backflow device the municipality may require you to have an “Air Gap” backflow device mounted before they issue you a meter.

Looks something like this…

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I’d need to run the hose directly to my PW. No tank. Will an “air gap” still be needed?

That’s pretty tricky Andrew. Hydrants put out 200psi more or less, you’ll need a valve somewhere “In Line” to valve down hydrant psi or you’ll blow the packings in your pump. Inlet psi on most pressure washers are around 50 psi or less, I pretty sure that’s right.

a few months ago, I saw a company working downtown who was doing this (running a line directly from a hydrant to their PW). I looked at the connection attached and it was pretty big, bulky and elaborate, but legit and allowing them to work. I wish I knew who they were and could now inquire how they did this, but I don’t recall their company name.

They hook up to the hydrant then run 200 ft of high pressure half inch hose this help reduce the pressure to the pressure washer btw i dont recommend doing this

I see the city workers doing this often but i can guarantee i would not be allowed to. And yes there is supposed to be an air gap to make sure there is no back flow for posible contamination of the water even though the meter you have to rent has a check valve

hydrant pressures are no different than normal house tap pressure ~35-50 PSI give or take location in the grid… and muniicipality. only difference is gallonage.

one word of advice - open and close the hydrants slowly, I usually go a half turn, switch hands and turn another half… never wanna close it fast - especially when flushing the hydrant, you can cause a water hammer… you muck up their pipes you gonna have one big bill on your hands…

Don’t ever hook up a hydrant straight to you inline feed to your pump. Have a water tank for the hydrant water to dump into. Also you better check for sure if you can even use the Hydrant. I had the local Municipalities tell me there’s no way they’ll issue a Powerwashing company the hydrant meter and yet they’ll issue them to Landscapers.

A few yrs ago we cleaned the majority of this towns walkways. I talked to the local municipalities including the town board even though I won this bid thru the towns bidding process they would not allow us to touch a hydrant. I had to have 2000’+ of garden hose handy to keep our tanks somewhat full. We had more cars ruin so much hose it was frustrating. It took us weeks to finish that nightmarish job.

Be sure you open all the way, if you don’t turn it all the way water will come through the weep holes and make a big hole around it.

Thanks guys for all the advice, I really do appropriate the valuable input. After thinking it over, it looks like it will be more hassle and difficult to go the hydrant route. Back to the drawing board!

Andrew, this would be one of the times a “Buffer Tank” set up would have saved this job. Might want to look into building one this Spring. It won’t be the last time you run into this problem.

Good Luck!

Absolutely right Guy. I’m meeting someone this afternoon to see if they can’t help me install one with my current set up. :slight_smile:

Hi guys,

Working a gig at the moment in NYC and came across this conversation. We’re working with the local regiment so we’re all good for permits, etc.

We want to hook a power washer up to a fire hydrant to clean the side walks. The armory officials say they’ve lost the part needed to attach a PW to the hydrant. Can anybody tell me what piece/s I need to hook it up?

Thanks in advance.

I’m quoting myself here. I would not advise hooking straight to a hydrant. Pressure washers have a maximum inlet psi that you should not exceed. Maybe Russ can jump in here with better words of wisdom.

And again having a buffer tank would easily solve this problem. Depending on the size pressure washer it could only have to be 50-75-100 gal tank.

Just Saying…

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Hey Keith-- you ever see my trucks out there in the big apple;)
I also have the hydrant permits. They don’t advise to do this but in a pinch if you just barely open up the hydrant you can have water run thru it at a low enough PSI to not harm your power washer. I have this piece here in my trailer Fire Plug Adapter from PowerWash.com

You also need the RPZ valve to control the back pressure.

Hydrants should be opened all the way or not at all.