A Flow Test Predicament

I've occasionally run into predicaments on projects that put me in a tough position. 

A couple weeks ago as part of a rural project in a small town outside of Memphis I was helping coordinate a flow test between a hired sprinkler contractor and the water utility.

I had initially asked both the fire and water department if they conducted tests or had interest in witnessing, asked for sprinkler contractor recommendations, and then called the nearest sprinkler outfit I could find (which happened to be an hour and a half drive away). They agreed to run a flow test for $500. I gave parameters on which hydrants I felt we needed tested and gave the go-ahead.

Results from the test were very poor. A static of 65 psi dropped to 40 at only 580 gpm, with the extrapolated curve showing a maximum capacity of around 800 gpm at 20 psi. 

Flow test results are dependent upon quality visual readings and calibrated equipment.

Based on the intent of the project with significant storage capacity (think ESFR), we were looking at both a pump and a tank to supplement both pressure and flow.

The hiccup came when I caught word from the water department who told the general contractor (our client) that the sprinkler company used a gauge that didn't zero out and the water department suspected was not calibrated. Based on past history the water department expected better flow in the area (at least), and were surprised that the flow had been so low.

Now to the minor dilemma - we need the test re-run (especially if there's water storage tank implications) - so does that mean having the same sprinkler contractor run the test again? The water department, after talking the situation with them, wasn't a big fan. Do I find another sprinkler contractor, and have to eat the original $500? Do I play the game that many general contractors would run, and not pay the $500?

Pressure gauges can become less calibrated over time - and the further they get from true readings
​the less reliable the resulting data becomes.

I'm not the kind of person that generally makes a phone call without some kind of directive or question in mind, but I called the contractor and just laid out what I had heard and asked how they wanted to handle it. Fortunately, the sales manager was extremely helpful and offered to re-run the test at no additional charge (despite the one-way 1.5 hour drive to the site) with a new set of gauges.

I'll get the results this week or next, and I suspect that with even slightly better flow information there could be big impacts on the sizing of water storage.

I was on the receiving end of generosity and being well-served in this case, and I am very thankful for it.

Being in business affords us the opportunity to make many decisions and serve other people. One of my favorite aspects of running a small team is having the opportunity to serve people very well and own our mistakes. Clients don't always expect perfection, but a full-fledged genuine effort to serve in a client's best interest usually results in successful projects and happy clients.

I don't expect every flow test, every installation, or every encounter to be perfect - but having people who are willing to own a mistake and take steps to correct it are the type of people I enjoy working with.

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