Forrester Heights Booster Station Rev 21231 FRYAR AVENUE
P.O. BOX 460
SUNINER, WASHINGTON 98390-1516
T. 253.863.5128 F. 253.863.0946
www.patametrix.com
November 21, 2007
PMX No. 247-1781-024
Mr. Jim Gibson, P.E.
City of Yelm
105 Yelm Avenue West
Yelm, WA 98597
ENGINEERING . 'ALANNING~ ENVIRONMENTAL SCIENCES
Re: Forrester Heights Water Booster Pump Station, Second Review
Dear Mr. Gibson:
We have completed review of the design submittal by KPFF for the Forrester Heights Booster Pump Station
received in our office November 5, 2007. The submittal included a revised Water Booster Pump Station dated
October 22, 2007 (Engineer's Seal Date), full size design drawings dated October 22, 2007 (Engineer's Seal
Date), and a Washington State Department of Health Project Approval Application Form (undated). We have the
following comments and recommendations based on our review:
COMMENTS
Revise the building and/or piping layout to allow adequate operator access to the pump skid, service
panel, and control panel. In the current configuration, an operator would have to step over above-slab
piping including a pressure release valve and hose bib to access the panels. Provide a minimum of 2 feet
of clearance on all sides of the pump skid. Please note that some of the comments and recommendations
in this letter will change the dimensions of the proposed equipment.
2. Revise the line types used for the in-building piping on Sheet C11.1. Drawings show dashed lines for
above-slab piping and the pressure tank.
As previously noted, indicate the type of joint restraint for the piping connecting the existing 10-inch
water main to the booster pump assembly, i.e. flanged connections, mechanical joint with megalug, etc.
4. As previously noted, provide a check valve on the discharge side of each pump. The appropriate type of
check valve should be determined based on the water hammer analysis noted below.
5. Provide a hose rack on the wall in the vicinity of the hose bib.
6. Provide a lifting strategy for removal of large equipment such as the pumps and bladder tank.
7. Provide an air gap for the drain line from the pressure relief valve per DOH standards.
Mr. Jim Gibson
November 21, 2007
Page 2
8. Draw the generator to scale in the plan view, including the enclosure. Provide a minimum of 3 feet of
clearance from the building and fencing to allow maintenance and fueling of the generator. Provide a
detail of the generator mounting slab.
9. The plans and project report indicate a 35 kW generator will be provided, while the equipment
specifications indicate 40 kW. Once all comments that could impact power requirements have been
addressed, provide load calculations to size the generator.
10. Provide the optional foam and sound scoop noise attenuation options on the generator.
11. Provide HVAC calculations to verify the exhaust fan and heater selection. Verify that the
24-inch-diameter gable vents will allow adequate airflow to enter the building.
12. Provide calculations (not estimates) of the fitting losses and head losses through the booster pump station
to verify pump selection is correct. Include the losses through the check valves requested in this letter.
13. Perform a water hammer analysis on the lift station and proposed Forrester Heights water distribution
system. The analysis should specifically address fire hydrant and system valve operation, normal pump
starts and stops, and pump stops due to power outage.
14. Provide bladder tank sizing calculations. Provide two smaller bladder tanks for redundancy.
15. As previously requested, provide a detailed control and instrumentation plan and control logic. Describe
the specific instrumentation and control components proposed for use in the system.
16, The plans indicate that the electrical systems will be bidder-designed. As previously noted, a detailed
electrical design must be provided to review adequacy of the system prior to approval of this project.
17. The electrical system will require review once the mechanical comments have been addressed. General
electrical comments are:
• Clarify the type of enclosures to be used for the control panel and transfer switch.
• Provide a minimum of 3 feet of clearance in front of the control panel and transfer switch.
• Provide weatherproof receptacles inside the pump station.
18. The Maintenance Chart included in the project report includes references to a well, well house, and
reservoir. Provide aproject-specific maintenance chart.
19. Has the DOH Project Approval Application Form been submitted yet? If so, provide all DOH comments
with the next submittal package.
Once these comments have been addressed and the additional information requested has been provided, we can
provide a more detailed review of the proposed pump station.
Mr. Jim Gibson
November 21, 2007
Page 3
RECOMMENDATIONS
• As previously noted, it appears that the pumps the applicant is proposing will meet the minimum
operating pressures required to respond to peak demands (30 psi residual pressure) and fire flow demands
(20 psi residual pressure). However, we would recommend that the City/applicant review the minimum
operating pressures that the booster station is sized for and consider increasing the expected operating
pressure to exceed minimum DOH requirements. Specifically, we recommend that the system be
designed to meet the 60 psi average residual pressure generally available throughout the City of Yelm
during peak hourly demand conditions.
• We recommend that the City consider inclusion of a water meter on the discharge of the booster station.
• As previously noted, we recommend that the control system for the booster pump station be tied into the
overall City SCADA system. The proposed visual and auditory alarm is not sufficient to ensure adequate
response to problems with the pump station. This effort may need to be completed by the City or the
City's agent.
To facilitate continued progress in the review of this project, we recommend a meeting including the City of Yelm,
Parametrix, the applicant, and the applicant's engineer to further discuss these comments and recommendations.
Please contact either of us if you would like to schedule this meeting.
If we can be of further assistance, please let us know. Thank you for the opportunity to review this project for you.
Very truly yours,
R MF"h IX
Rai y Ray end, P.E.
Senior Engineer, Municipal Services Group
Very truly yours,
PARAMETRIX
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Michael T. Ollivant, P.E.
Water Solutions Program Manager
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cc: Project File