Yeah, no kidding. What has to happen is that the flow rates at fill need to be reduced and start times staggered, it would seem. And start filling those tanks sooner to keep them topped, perhaps? Or completely redesign the municipal system at a cost of dozens or hundreds of millions of dollars to this small community and drag the project out three years over schedule and then ... sorry, you have to remember I live and work in San Diego.
Steve Leyton Protection Design & Consulting -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Todd Williams - FPDC Sent: Monday, October 01, 2007 2:19 PM To: [email protected] Subject: RE: water supply fluctuation The large user (Indian Casino) is filling their private tank. There are also two municipal tanks that get filled via this line, so I'm not sure how much impact regulating draw is going to have when any one or all three could be on line at the same time. I'm glad I didn't design the Home Depot down the street. At 05:05 PM 10/1/2007, you wrote: >Have several water supply/flow test/ambient condition discrepancy >stories, but I'll save them for another time. The closest situation I >had to this was where a sporadic condition was occurring on a water main >system that fed "drop tanks" that served an agricultural user whose land >abutted the industrial park in which we were working. In that case, >an adjustment was made in the fill system that served the tanks, which >sounds like it might apply here. Are you saying that a large user >consumes water in the public tank(s), that cause the water level and >thus the static elevation head pressure to drop, or is it that the >municipal system drops radically in resid' when it starts to fill the >user's private tank(s)? If that's the case, then the private system >can be modified to come on sooner and fill for longer periods at lower >flow rate and pressure and/or put on a timer so that the auto-fill would >run at off-peak hours. > >Steve Leyton >Protection Design & Consulting > > >-----Original Message----- >From: [EMAIL PROTECTED] >[mailto:[EMAIL PROTECTED] On Behalf Of Todd >Williams - FPDC >Sent: Monday, October 01, 2007 1:30 PM >To: [email protected] >Subject: water supply fluctuation > >I just ran into a situation that makes me a little nervous about >water department flow tests. I have been asked to straighten out a >mess on a system in a 7 story condo (multiple issues). A designer who >was asked to verify some hydraulics got a flow test from the >municipality which was about 23 pounds higher than the design test, >which was done several years ago. At that time, she was told this was >due to improvements in the public system. They had been doing a lot >of work on the system, so it was believable. System pressure gauges >were with a reasonable number of the static pressure. When I got on >board, I also checked with the water department and was told the same >thing. Recently, a contractor working on the system noticed the the >pressures reading lower. Upon further investigation, including >pressure recorders on hydrants, it was found that the pressures >varied 30 psi over a 3 day period. The water department was not aware >of the range of fluctuation until they did this test. Their >explanation was various pumps kicking in to fill tanks, including for >the town's largest water user. Now we are going back and >re-calculating the systems with a much lower static pressure. Has >anybody run into this type of thing? Is there a good way to detect >it? I consider myself fairly savvy and sniffing out problems, but >this caught me off guard. How can a water department not know this >type of thing is going on. This is a small city in CT. > >Todd G. Williams, PE >Fire Protection Design/Consulting >Stonington, Connecticut >www.fpdc.com >860.535.2080 >_______________________________________________ >Sprinklerforum mailing list >[email protected] >http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > >To Unsubscribe, send an email >to:[EMAIL PROTECTED] >(Put the word unsubscribe in the subject field) >_______________________________________________ >Sprinklerforum mailing list >[email protected] >http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > >To Unsubscribe, send an email to:[EMAIL PROTECTED] >(Put the word unsubscribe in the subject field) Todd G. Williams, PE Fire Protection Design/Consulting Stonington, Connecticut www.fpdc.com 860.535.2080 _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
