Loading...
FW Forrester Heights Booster Station ReviewIPM.Note FW: Forrester Heights Booster Station Review FW: Steve Harrington Mike Ollivant Steve Harrington SMTP MOllivant@parametrix.com Forrester Heights Booster Station Review EX /O=CITYOFYELM/OU=FIRST ADMINISTRATIVE GROUP/CN=RECIPIENTS/CN=STEVEH EX /O=CITYOFYELM/OU=FIRST ADMINISTRATIVE GROUP/CN=RECIPIENTS/CN=STEVEH Microsoft Mail Internet Headers Version 2.0 Received: from psmtp.com ([64.18.0.114]) by server1.ci.yelm.wa.us with Microsoft SMTPSVC(6.0.3790.3959); Wed, 9 Jul 2008 10:22:04 -0700 Received: from source ([216.32.181.16]) (using TLSv1) by exprod5mx228.postini.com ([64.18.4.10]) with SMTP; Wed, 09 Jul 2008 12:19:46 CDT Received: from mail126-wa4-R.bigfish.com (10.8.14.252) by WA4EHSOBE005.bigfish.com (10.8.40.25) with Microsoft SMTP Server id 8.1.240.5; Wed, 9 Jul 2008 17:19:46 +0000 Received: from mail126-wa4 (localhost.localdomain [127.0.0.1]) by mail126-wa4-R.bigfish.com (Postfix) with ESMTP id 3A428E04E0 for <steveh@ci.yelm.wa.us>; Wed, 9 Jul 2008 17:19:46 +0000 (UTC) X-BigFish: VPS-35(zzfeeM7efV18c1K1fa4L145fMzz10d3izz186Mz2dh6bh) Received: by mail126-wa4 (MessageSwitch) id 1215623980664142_5898; Wed, 9 Jul 2008 17:19:40 +0000 (UCT) Received: from scan.parametrix.com (scan.parametrix.com [209.164.172.13]) (using TLSv1 with cipher RC4-MD5 (128/128 bits)) (No client certificate requested) by mail126-wa4.bigfish.com (Postfix) with ESMTP id 6FAEAB0079 for <steveh@ci.yelm.wa.us>; Wed, 9 Jul 2008 17:19:40 +0000 (UTC) Received: from CORPHUB02.parametrix.com (172.24.10.125) by CORPEDGE01.parametrix.com (209.164.172.13) with Microsoft SMTP Server (TLS) id 8.1.240.5; Wed, 9 Jul 2008 10:19:42 -0700 Received: from CORPEXCHMB01.parametrix.com ([10.10.10.11]) by CORPHUB02.parametrix.com ([172.24.10.125]) with mapi; Wed, 9 Jul 2008 10:19:39 -0700 From: Mike Ollivant <MOllivant@parametrix.com> To: "steveh@ci.yelm.wa.us" <steveh@ci.yelm.wa.us> CC: Randy Raymond <RRaymond@parametrix.com> Date: Wed, 9 Jul 2008 10:19:37 -0700 Subject: FW: Forrester Heights Booster Station Review Thread-Topic: Forrester Heights Booster Station Review Thread-Index: AcirtPnCaOiS613gRkCp6UcgFPl/qQGW/nnQC/W/sGA= Message-ID: <85B8A2F0F0B8DE47B11EE876D3CEBA4A311088606D@CORPEXCHMB01.parametrix.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: multipart/alternative; boundary="_000_85B8A2F0F0B8DE47B11EE876D3CEBA4A311088606DCORPEXCHMB01p_" MIME-Version: 1.0 Return-Path: MOllivant@parametrix.com X-pstn-neptune: 0/0/0.00/0 X-pstn-levels: (S:99.90000/99.90000 CV:99.0000 R:95.9108 P:95.9108 M:97.0282 C:98.6951 ) X-pstn-settings: 5 (2.0000:2.0000) s cv gt3 gt2 gt1 r p m c X-pstn-addresses: from <MOllivant@parametrix.com> [19/1] X-OriginalArrivalTime: 09 Jul 2008 17:22:04.0375 (UTC) FILETIME=[4E61BE70:01C8E1E8] --_000_85B8A2F0F0B8DE47B11EE876D3CEBA4A311088606DCORPEXCHMB01p_ Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable --_000_85B8A2F0F0B8DE47B11EE876D3CEBA4A311088606DCORPEXCHMB01p_ Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable --_000_85B8A2F0F0B8DE47B11EE876D3CEBA4A311088606DCORPEXCHMB01p_-- Mike Ollivant SMTP MOllivant@parametrix.com Randy Raymond Steve Harrington Forrester Heights Booster Station Review From: Jim Gibson [mailto:jimg@ci.yelm.wa.us] Sent: Friday, May 09, 2008 2:06 PM To: Clint Pierpoint Cc: Steve Chamberlain; RGD; Mike Ollivant; Grant Beck Subject: Forrester Heights Booster Station Review Clint - After reviewing your requests, please see the information below. 1. The City will accept a 2” connection to the hydropneumatic tank. We would require that prior to booster station acceptance by the City conduct a start up test that demonstrates reliable system operation. 2. The City has considered your request however we feel that installation of this check valve is in the best interest of the City and City water system. 3. The City requires all pumps to have a VFD controller. I have had conversations with Clint and yourself about the VFD controller being able to control multiple pumps with one controller. If this is the case then an additional controller will not be needed. It is unclear at this time if one VFD will actually control all four pumps. We should have a better understanding of the VFD operation when you submit the detailed control logic document with the manufactures submittal. At this time I feel it is prudent to move ahead with the approval and submittal process and resolve this during the review of the control logic. 4. City will accept one hydropneumatic tank for installation in this booster station. However please note that 2 or more may be required for the Tahoma Terra Water Booster Station. With this information we are at a point that the construction documents appear to be complete enough for construction of this station. I have forwarded the submittal to DOH and have followed up verbal discussion with the DOH reviewer. I am expecting to have either an approval or additional comments from DOH by early next week. If they do not have any additional comments we will proceed with the signature of the plans and construction of the water booster station building. If you have any questions please do not hesitate to contact me. Jim Gibson P.E. City of Yelm, Development Review Engineer PO Box 479 Yelm,WA. 98597 Ph. 360.458.8438 Fx. 360.458.3144 jimg@ci.yelm.wa.us ________________________________ From: Clint Pierpoint [mailto:clint.pierpoint@kpff.com] Sent: Thursday, May 01, 2008 10:59 AM To: Jim Gibson; Grant Beck Cc: Steve Chamberlain; 'RGD' Subject: Forrester Hieights Booster Station Review Water Hammer Analysis Jim, On behalf of the project proponent, I would like to request clarification on the recommended changes to the Forrester Booster station piping identified in the Parametrix Technical Memorandum dated April 24, 2008. 1. The memo indicates the power outage pump shutdown water hammer analysis was performed by stopping all three large pumps at once at 1,660 gallons per minute. The maximum system demand is 867 gpm. All three large pumps are not intended to operate simultaneously, two will meet fire flow demands and one is redundant and would only operate if one of the other pumps failed. However, the analysis resulted in acceptable pressure levels without a pressurized surge tank. The submitted design proposes a pressure tank that will reduce pump cycling during low-flow conditions and dampen potential surges during normal operation. The technical memo suggests increasing the line size between the main and the proposed pressure tank to 4-inch “will improve the ability of the surge tank to perform these functions” and cites the results in Appendix B. The referenced Appendix B graph reflects results for an analysis of a Power Outage Pump Failure at 1,660 gpm. Normal operation of the booster pump station will be at 0-117 gallons per minute. The analysis does not support the recommendation. The connection port on the proposed bladder tank is 2-inch, we propose increasing the line size to this limiting condition to maximize operational function of the tank. 2. The memo also recommends the installation of an 8-inch check valve with normally open isolation valves on either side, connecting the suction and discharge manifolds which would allow some minimal domestic flow and allow fire flow to be pumped through the booster station in the event of complete pump station failure. Although the described scenario is implausible, the intent of the described conditions could be sufficed by manipulating the valves already included in the piping configuration proposed. There is a 10-inch bypass installed in the watermain between the suction and discharge stubs to the booster station which would allow more water to be available downstream rather than realizing the head losses through the booster station. This is a very expensive alteration to the proposed piping layout and there is no engineering analysis provided in the technical memo to support the recommendation. 3. The operation of the proposed redundant booster pump would be in a fourth call position in the event of a pump failure and a fire flow demand. The pump would start (across-the-line) in a third position as demand exceeded the capacity of two pumps. The VFD’s on the other two pumps would adjust to maintain the system demand. The recommendation of a soft starter on the redundant booster pump is not supported in this report. 4. It is recommended in the memo that the City consider requesting a spare 132-gallon pressure surge tank. As demonstrated previously in the memo, the power shutdown analysis resulted in acceptable pressure levels without a pressurized surge tank. The booster pumps have variable frequency drives and can operate without pressure tanks for a limited period of time for tank maintenance or replacement. Pressure tanks of this size have a life expectancy of eight to twelve years. Degradation of an unused tank stored for that length of time would likely result in an unusable product when needed. In addition, an adequate interim pressure tank is available off-the-shelf at most any plumbing supply and hardware stores. Thank you for consideration in this matter. Please provide direction on these items at you earliest opportunity so we are able to amend our plans accordingly keep this project moving. If you have any questions, please don’t hesitate to contact me. Cordially, Clinton D. Pierpoint | Associate KPFF Consulting Engineers 4200 Sixth Avenue, Suite 309 Lacey, Washington 98503 O: (360) 292-7230 M: (360) 790-6832 F: (360) 292-7231 clint.pierpoint@kpff.com <mailto:clint.pierpoint@kpff.com> www.kpff.com <http://www.kpff.com> <85B8A2F0F0B8DE47B11EE876D3CEBA4A311088606D@CORPEXCHMB01.parametrix.com> FW%3A Forrester Heights Booster Station Review-2.EML Steve Harrington Steve Harrington EX /O=CITYOFYELM/OU=FIRST ADMINISTRATIVE GROUP/CN=RECIPIENTS/CN=STEVEH steveh steveh@ci.yelm.wa.us SMTP steveh@ci.yelm.wa.us Randy Raymond SMTP RRaymond@parametrix.com Randy Raymond Randy Raymond