ITEM 3.7 Lift station #3P
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MINNESOTA V
DEPARTMENT INFORMATION
Request for
City Council Action
ORIGINATING DEPARTMENT:
REQUESTOR:
MEETING DATE:
Utilities
Kurt Neidermeier
April 27th, 2015
PRESENTER(s):
REVIEWED BY:
ITEM #:
Consent Agenda
Lori Johnson
3.7 Lift Station #3 Improvements
AGENDA ITEM DETAILS
RECOMMENDATION:
The Public Works Subcommittee reviewed the Barr Engineering proposal for electrical design services
for Lift Station #3 improvements and recommended approval at the April 22, 2015 meeti
ARE YOU SEEKING APPROVAL OF A CONTRACT? I ISA PUBLIC HEARING REQUIRED?
No. I No.
BACKGROUND/JUSTIFICATION:
The 2015 Capital Improvement Plan includes a Utility project to increase pumping capacity at Lift Station
#3 (Project # UTIL-12-075). The Lift Station serves the growing population in the West Sanitary District
conveying all its wastewater to the West Wastewater Treatment Facility and is anticipated to reach
capacity in 2016.
The Sewer Fund has allocated $85,000 dollars in 2015 to increase Lift Station #3 capacity. The project
provides the installation of an existing 40 horsepower submersible pump, three variable frequency
drives, control cabinet and instrumentation services for control functions and alarms.
Stuart Stephens of Barr Engineering has provided review of the project and prepared a proposal with
project estimates. The proposal provides electrical plans and schematics, Division 16 electrical
specifications, assistance with any addendums, shop drawing review for electrical equipment and final
inspection for a total not to exceed amount of $8750.00.
Engineering Estimates:
Engineering $ 8,750
Construction Costs (per proposal) $44,850
Project Estimate $53,600
Additional cost to the project is the installation and start up services of the existing pump at an estimate
of $2000 for a total project estimate of $55,600.
Staff has worked with Stuart Stephens on other projects including lift stations and well houses and is
comfortable recommending acceptance of the proposal. Staff will solicit quotes from several
contractors and provide recommendation at the June Public Works Subcommittee for the June 22nd
Council approval.
SUPPORTING DOCUMENTS: X ATTACHED ❑ NONE
Barr Engineering Proposal of Services Lift Station 3 Improvements
POSSIBLE MOTION
Please word motion as you would like it to appear in the minutes.
Motion to approve Barr Engineering Proposal for Engineering Services for Lift Station #3 Improvements.
BUDGET INFORMATION
FUNDING:
N/A
ACTION TAKEN
❑ APPROVED AS REQUESTED ❑ DENIED
ENTS:
BUDGETED: ❑ YES
❑ NO
❑ TABLED ❑ OTHER (List changes)
resourceful. naturally. BARR
engineering and environmental consultants
Memorandum
To: City of Otsego
Attn: Kurt Neidermeier
From: Stuart Stephens
Subject: Otsego, MN Lift Station 3 Proposed Improvements
Date: March 27, 2015
This memorandum outlines the existing conditions at Otsego lift station 3, the planned upgrades, and our
proposed fees for electrical engineering design services.
Existinz Conditions and Planned Uperades
The existing lift station has provisions for operating up to three lift station pumps, along with one well
pump. All motors are currently operated with electronic soft starters, but it is desired to convert the lift
station pumps to variable frequency drives (VFDs), to try to maintain a more constant flow rate to the
adjacent wastewater treatment plant. The lift station site was inspected on February 26, 2015; my notes
from that visit are included below for reference.
• The existing lift station control panel enclosure is 72" W x 60" H x 16" D, plus 18" high legs.
• The concrete pad extends 32" in front of existing panel, plus about 12" to either side.
• The main circuit breaker in the control panel is 400 amps. The standby circuit breaker for the
generator receptacle is 200 amps
• Lift station pumps 1 and 2 have 100 amp circuit breakers. Lift station pump 3 and well 5 have
150 amp circuit breakers
• The lift station currently has two soft starters for lift station pumps, and one soft starter for well
pump. There is space for a third lift station pump soft starter, but it has not yet been installed. It
appears #4 wire was used to connect the branch circuit breakers to the soft starters.
• The lift station currently has two 20hp lift station pumps. Those two pumps will remain in place
for now, and a third 40hp pump will be added. Ultimately, it is anticipated that all three pumps
will be upgraded to 40hp.
• Plan on adding three 40hp VFDs, plus allowing space to install a future VFD for the well pump.
There isn't enough space inside the existing enclosure to accommodate VFDs, so they will be
installed in a separate enclosure, mounted back-to-back with the existing enclosure.
o For reference, the approximate sizes of 40hp VFDs from several manufacturers are:
■ Allen-Bradley PowerFlex 753: 19" H x 9" W x 9" D.
■ ABB ACH550: 27" H x 8" W x 10" D.
■ Yaskawa A1000: 19" H x 10" W x 10" D.
■ Typical weight of a 40hp VFD is about 55 lbs.
Barr Engineering Co. 4700 West 77th Street, Suite 200, Minneapolis, MN 55435 952.832.2600 www.barr.com
To:
Kurt Neidermeier / City of Otsego
From:
Stuart Stephens / Barr Engineering Co.
Subject:
Otsego Lift Station 3 Improvements
Date:
March 27, 2015
Page:
2
• The existing branch circuit breakers for the lift station pumps can be reused, and simply
reconnected to the input terminals of the new VFDs. The existing soft starters can be
disconnected and remain in place; if something happens to a VFD in the future, the associated
soft starter can be easily reconnected if necessary to maintain pump operation.
• The existing programmable logic controller in the lift station control panel is an Allen-Bradley
MicroLogix 1500. It has about 6 spare digital inputs, about 6 spare digital outputs, 2 spare analog
inputs, and no spare analog outputs. Additional analog I/O modules will have to be added to
allow for speed control of the new VFDs.
• The method of pump control to be used after the VFDs are installed is yet to be determined. Two
possible methods are:
o Varying the VFD speeds based on wet well level, to maintain a constant level in the wet
well.
o Varying the VFD speeds based on influent flowrate to the wastewater treatment plant.
This would be similar to the control method used at Quaday lift station 1, but there is a
flow meter located right at that lift station. At this lift station, the flow rate would have to
be transmitted via radio fiom the wastewater plant PLC to the lift station PLC. There
would be some time delay between when the flow rate value is measured and when the
lift station PLC receives that value; in addition, if communication was lost the flow rate
signal would not be available until radio communication was restored.
o No matter what method of control is used, it may be advisable to run the pumps at full
speed periodically, to help prevent settling in the pipes.
• The City of Otsego currently uses AE2S for programming support of the SCADA system. The
contact person at AE2S is Alan Dostal, 612-209-0491.
• Estimated construction costs:
o Three 40hp VFDs at $7,750 / each $23,350
o One analog I/O module for PLC $2,000
o Stainless steel enclosure with ventilation $7,500
o Installation and wiring $4,000
o Programming, modifications to existing SCADA and startup $5,000
o Miscellaneous other costs $3,000
Estimated construction cost total: $44,850
To:
Kurt Neidermeier / City of Otsego
From:
Stuart Stephens / Barr Engineering Co.
Subject:
Otsego Uff Station 3 Improvements
Date:
March 27, 2015
Page:
3
Proposed Scope of Services
Barr Engineering Company proposes to provide the following engineering services:
1. Preparation of press -ready electrical plans and schematics.
2. Preparation of press -ready Division 16 electrical specifications. This proposal does not include
preparation of the general and special conditions for the specifications.
3. Due to the estimated construction cost, it is assumed the project will not have to be publically
advertised, and as such the City will simply solicit bids from several contractors. Therefore, it is
assumed general and special conditions for the specifications, as well as any other standard bidding
documents normally used for publically advertised projects, will not be required.
4. We will field calls and answer questions which may arise during the bid phase of the project, and will
assist in preparing any necessary addendums.
5. Construction phase services will include shop drawing review for the electrical equipment. We will
make one final inspection visit after construction is completed. We will field calls and answer
questions from the contractor during construction, and assist in preparing any necessary change
orders.
Proposed Fees
Barr Engineering Company proposes to provide the described services on an hourly basis for the
following not to exceed amounts:
DesignPhase................................................................... $5,500
BidPhase........................................................................ $750
Construction Administration Phase ................................................. $2,500
Services will be billed monthly.
Thank you for the opportunity to present this proposal. If you have any questions, comments or revisions,
please call.