It seems like these thieving contractors could find a more secluded target for their pilferage. I’d assume that a Home Depot lot is under camera surveillance.
I’m wondering if the city and HD had an agreement for hydrant water supply in the Garden Dept, then a falling out and a lock to seal the deal…?
Backflow preventers on residences wouldn’t do anything to prevent this – the poison would be in the normal water main, which is properly flowing forward into the residence. (Normally, residential backflow preventers are in outgoing lines, to prevent sewer water from flowing backwards and flooding into the house.)
Not if you know how to block the camera. My (ex)BIL’s truck got got robbed a few years ago of all it’s tools at a Home Depot. When the police checked the cameras, they found the the person that did it parked a big van between the surveillance cameras and his pickup and the cops couldn’t see anything. My guess would be that the reason those locks are there is to prevent landscaping or cement companies from tanking up while they’re there.
While there are backflow preventers for sewage lines, they also have them for incoming water lines. Some cities install them in the main line running to your house, but most places don’t do that. At my work, we’re are required to install a backflow preventer (you can get them at Home Depot) on all of our hose spigots and technically any faucet that doesn’t have a certain amount of air gap (8 inches maybe?). The reason being that if there is ever a water main break or someone opens a hydrant and plugs a pump into it (like a fire truck) or does anything that puts a negative pressure on the water system any open faucets will suck air into them. If the open faucet happens to be in something (say, a hose sitting in a bucket of mop water) it’ll draw that into the mains.
They are required on incoming water lines. Water heaters must be protected with expansion tank due to them.
In addition to the water theft issue, the thieves will tend to use whatever wrench they have available (spanner, pipe wrench) which tend to damage the brass valve stem in the hydrant.
Fire departments have special hydrant wrenches which apply equal pressure to all four sides of the stem, preventing damage.
To take it another step, when people that shouldn’t open hydrants close them too quickly the water hammer effect can shatter old pipes under the road causing even more problems…or so I’ve heard.
Well I for one would not enjoy reading anyone’s theory on how to poison the populace.
I remember back when I was a new firefighter 30 years ago when a statement was made as to why we were not connecting a hard suction hose between the pumper and the hydrant, back in that time we were laying 2 1/2 inch soft hose for hydrant lay.
One of the oldtimers stated that we would suck the water out of all the toilet reservoirs in town. 
Being young and ignorant, I believed him! Hey, that’s how we learned back then. There was only a annual sectional school that was elective.
Locks are EYE WASH!
Water hammer can certainly be a problem. I was once doing a public water test at a hydrant and the fire dept chief shut the hydrant off too quickly. When we went to a nearby restaurant for lunch an hour or so later they had no water, no coffee, no soft drinks. All because water hammer had roiled up the water in the towns gravity tank!
This was a small town, and everyone in the restaurant was giving us dirty looks for spoiling their dining experience. 
::Looks up “roil” on Google:: Huh, that’s a real word.
Every summer on the news they talk about people turning on the hydrants to cool off and warn people of all the reason that they shouldn’t be doing it. One of the reasons they give is that if you improperly shut it off (too quickly) you can shatter the pipes. I know running a hydrant will stir up crap in the water system, they always tell us that when they test the system every few years (but I’ve never noticed it). What I’m just no wondering is if it’s possible for a person to shut off a hydrant, with a wrench, fast enough to shatter underground pipes. I’ve never turned a hydrant on or off, so I have no idea how easy or hard it is to do.
I don’t think anyone answered this yet. The fire hydrants and the water supply to your house are on the same line. So yes, if you can feed something, by whatever method, into a hydrant, it will get into the general water supply, nothing tin foily about it.
I don’t have any personal experience with damaged underground mains, but I suppose it’s possible. If a main is damaged by water hammer, it probably is already old and has other pre-existing issues which leave it susceptible to damage.
I really thought i explained it back in post #18
But those locks! You can shoot them with a bullet and they won’t open!!! I’ve seen it on TV!
Yeah, but I just wanted to make sure Postcards, understood that the hydrants and kitchen sink are both on the same system. They both tap into the same underground mains.
I could also think of a hundred other ways to do this without backing anything publicly right up to a hydrant. There are hordes of abandoned houses in the country and tapping into the water in a secluded basement is a lot more credible of a scenario.
If you were to ask me, I bet some contractors were turning on the hydrants in the parking lot to wash equipment, trucks, etc. and playing havok with the water table.
Many municipalities want all the water used to be metered, even if they are not charging for it. They meter the water at all the inputs to the system, and meter all the use. If there is a mismatch they start trying to track down the reason…either theft or a leak. When the hydrants are used for a fire they try to estimate the consumption if the hydrant is used to feed nozzles directly..if the hydrant is used to supply a pumper truck, then the truck meters the use.
In my city it is possible for people in outlying areas to get hydrant permits. They fill large tanks and transport the water for domestic use. They keep a log and report how much they took. It is the honor system, but if the city cuts them off they are screwed. The two people I have known who used this system were extremely scrupulous in their reporting. The same is done for some construction contractors. It may be that HD did not want the contractors tanking up in their parking lots so had the hydrants locked.
Possibly because the valves are brass and brass is valuable. Thieves steal them for the scrap.
Wouldn’t the “Jaws of Life” snap off the lock instantly? If not, a simple bolt cutter should do it. I’m sure all fire trucks carry them. (Well, pretty sure)
Padlocks? Not having one around I wanted to destroy, I sliced the end off a 1/4’’ high speed twist drill with my cordless Dremel. It took 7 minutes. Guess the firemen would want something quicker. A sledge hammer quickly removes all but the very best.
I figure the drill is about the size and hardness of many padlocks.
Grrrr, I know this is out of proportion but I want people who steal such fixtures to be executed by being stabbed with a punji stick (dipped) and left to die in a dirty room heated to 130 degrees. (F)