Chlorination of an underground fire main downstream the double check valve and fire pump?

[SprinklerDesigner2]

What we have is an existing industrial park with about 20 buildings comprising approximately 1.5 million sq ft.

Fire protection consists of a fire pump and double detector check valve assembly at the property line and the problem is the water purveyor requires chlorination of a new extension to the system which is something I have never had to deal with downstream a backflow assembly. The fire department connection is on the pump house.

Just curious to know if anyone else had to deal with this type situation anywhere?

 

[cdafd]

Nope

May want to ask higher ups??

Just to clarify, once it goes past the check at the property line, there is no domestic tapped off of it??


If you have to do it, see if they will let you isolate your new work and test that only.

 

[SprinklerDesigner2]

This is a totally dedicated fire protection line without any domestic water taken off downstream the backflow assembly. If so every time a toilet was flushed or someone took a sip of water the fire pump would start and the fire department would be called. Of course this is assuming the jockey pump wouldn't keep up.

Pressure at churn is 170 psi.

 

[chicopee]

I have never heard of chlorinating a fire line but in the past, we had recommended antifreeze solution. Could there be a mistake in the request?

 

[stookeyfpe]

My water utility requires a chlorine residual test based on the Texas Commission on Environmental Quality regulations for Public Water Systems. This issue comes up occasionally when private fire hydrants are not separated from potable water supplies by a backflow preventer. Water purveyor laws vary around the country. Is potable water being supplied from the fire protection system, because this is the newest pain in the posterior trend we're seeing.

 

[SprinklerDesigner2]

There's a 12" dedicated suction line feeding the fire pump and upstream the 1,250 gpm fire pump there is an Ames 3000ss double detector check valve assembly. The reason for the 12" suction line was to maintain a minimum 20 psi suction at the fire pump per the Georgia Fire Marshal regulations.

The suction line was chlorinated when installed 5 years ago and I fully understand the need for that.

All private hydrants and fire sprinkler systems are fed from the dedicated fire grid downstream the double detector check backflow that serves no domestic water whatsoever.

I don't know how I am going to get this passed as there has to be at least one mile of underground, downstream the backflow, that has been added to over the years and non of that was ever chlorinated.

 

[stookeyfpe]

Suggestion 1: client needs to retain a GA registered PE licensed in Civil Engineering. I suspect the Civil Engineer can resolve this in short order.
Suggestion 2: provide the water purveyor with the shop drawing(s) illustrating the site layout and location of the DCVA. I understand water utilities can be persnikity but my utility is at least open to discussing the issue.