Installation of Backflow Valves & Sub-Metering All the Watermeters

Here is my situation: The Water Authority requires all the commercial, industry and residential accounts to install the Backflow Prevention Valves. We have 3 master water meters at the park and 2 of them are underground in small pits. I received two quotes from local licensed plumbers @$9-11K range. The high price is due to them needing to dig bigger pits to fit these valves, to lay concrete down to prevent the Spring water from getting into one of the pits, etc. At the same time, Sub-metering all the water meters is on my To-Do list as well. Since Sub-Metering the meters is a big project anyway, I’ve considered skipping installation of the Backflow valves on the master meters, and instead, try sub-metering the meters while installing the backflow valves on each tenants’ meter? Using this method, I can resolve two issues together, plus it is more cost effective in the long run. What is your opinion of this plan? Has anyone tried it this way before? Thanks in advance.

That’s seems like an awful lot for a backflow preventer. How big are they recommending this pit be, and have you looked to see how much an excavation company would charge to do that part?

Plumbers connect pipes and don’t move dirt and as a result always sub that out and have you pay a premium. Get more bids.

I would prefer installing one backflow preventer instead of 30 if the law allows it.

Backflow prevention asseblies must be tested once per year usually. Usually $20 to $50 per test do you really want that expense on 30 assemblies? The 9 to 11k quote for 2 backflow assemblies is crazy high. I get the issue of spring water filling the boxes with the backflow assembly. Code usualy states assemblies must not be submerged. One solution would be to plumb the assemblies above ground.

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@jhutson & @PhillipMerrill: The Backflow annual testing fee for commercial is $150-200/unit, residential is $20-30/unit, and can be passed to the tenants if I sub-meter them. I will try to obtain more quotes on this project, and double check with the water authority as well. Thanks for your input.

Many states allow centralized fees to support the operational service to be passed along too - they won’t allow things like registration fees, connection / disconnection fees, etc. In the end it will be cheaper month over month for your tenants to do a single one centrally, and you will be more likely to maintain it better than they will anyway.

I liked @PhillipMerrill’s suggestion about doing it above ground. Doghouse + backflow preventer + insulation + plumbing sounds like a 500 dollar job to me. Challenge the plumbers to do it simpler and know the state requirements before having them give you a bid so you can keep them honest. Sometimes these guys need to be told how to do their job otherwise they give you a gold plated solution when you need aluminum.

Good luck.


Give me a call and we would be happy to consult you.

We have over 24 years of service experience on the topic

800.697.9096 EXT 14

Has anyone used ABT to recommend their services? The one park that ABT worked on, the manager said the verdict is still out. So wanted to hear others experiences. I am sure whether it is good or bad, ABT would love to improve their services.

@GabeABT, would welcome any references that you can share as well?

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Did the city specify the size and type of each backflow assembly.
2" double check is $365 plus shipping

3" double check valve $1158.00 plus shipping

But if i was doing the work (which im not because I only work in Oregon :slight_smile: there would be a 50 to 100% mark up on parts plus labor. If the mainline is already dug up and exposed its still an all day project for 2 or 3 assemblies. This is the above ground option I suggested ealier.

My point is what size is the mainline as 3" is triple the 2" price.

Phillip Merrill
Merrill Water Systems

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Most likely a main backflow is required at the main municipal meter, which normally would suffice for your whole property. Sub-metering with individual back flows normally cost less than $125 (3/4’’ supply line) plus labor. However may not meet the requirements of your municipal supplier.

If freezing is not an issue raising the backflow device above ground, outside the parameter of your existing meter pit may be an economical option.
Also, note their are on going fees to test and certify the main municipal backflow device.

We’re here to answer your water sub-metering questions.

Dan Helton
Southern Water Management
727-827-4509, 421-9695