ITEM 7.2 East WWTF0
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MINNESOTA
DEPARTMENT INFORMATION
Request for
City Council Action
ORIGINATING DEPARTMENT: _
REQUESTOR:— --
MEETING DATE:
Administration
Lori Johnson, City Administrator
March 14, 2016
PRESENTER(s):
REVIEWED BY:
ITEM #:
Scott Schaefer, Project Engineer,
7.2
AE2S
AGENDA ITEM DETAILS
RECOMMENDATION:
Recommend proceeding with advertisement for bids for the East Wastewater Treatment Facility
(WWTF) Oxidation Aeration Improvement project.
ARE YOU SEEKING APPROVAL OF A CONTRACT?
Engineerinl? Design Agreement
IS PUBLIC NEARING REQUIRED?
No
BACKGROUND/JUSTIFICATION:
The 2016 Capital Improvement Plan includes funding for increasing installed redundant treatment
capacity at the East WWTF. The total project cost was estimated at $235,000, but as Scott Schaefer
explains below, the cost estimate has risen due to changes in the scope of the project. Due to the long
lead time for equipment, the recommendation is to bid the project as two separate bid packages.
Below is additional information on the project as prepared by Scott Schaefer:
The East WWTF solids treatment capacity was analyzed in 2015 to determine if capacity
issues similar to the West WWTF might be present at the East WWTF. The findings of the
solids capacity analysis have previously been presented. As part of that analysis, it was
determined that the flows at the East WWTF were approaching the levels that would be
above the firm capacity of the oxidation ditch (aeration) system (i.e. insufficient capacity
with the largest unit out of service). To re-establish redundant capacity, installation of
another large oxidation ditch was recommended and included in the 2016 CIP. This
equipment installation is consistent with the intent of capacity phasing at the East WWTF.
Action on this aeration equipment was on hold pending the outcome of the West WWTF
project bid opening.
Updated Information.:
• Favorable bids on the West WWTF digester expansion have provided overall budget
clarity to move forward with the East WWTF aeration equipment.
• A budget estimate was prepared in 2015 based upon limited information, and additional
preliminary investigation has refined the scope of the necessary equipment to operate
an additional oxidation ditch. Two additional large gates are required (effluent gate and
bypass/recycle gate) for an operational system as well as additional electrical work to
provide power and junction boxes to the mixer equipment (already owned) at the
appropriate locations.
Initial budgetary information was obtained from two equipment manufacturers to
further refine the opinion of cost.
Probable construction cost has risen from approximately $200,000 to a range of
approximately $300,000 to $350,000 with the changes in the scope of the project. Note
that this is still a preliminary cost opinion without the benefit of preliminary engineering
and there are many electrical unknowns of existing conditions to be confirmed.
Draft Project Schedule
i. The aerator equipment (specifically the gear box) is a long lead item, which
drives the schedule and procurement approach.
ii. Note that the equipment delivery schedule falls in early October, which is the
preferred time to remove liquid digested biosolids from the existing tank to
avoid multiple biosolids transfers.
Draft Aerator Schedule
Process
Equipment
General
Construction
Authorization to prepare bid documents
March 14, 2016
March 14, 2016
Sid Advertisement
March 31, 2016
April 25, 2016
Bid Opening
April 21, 2016
May 16, 2016
Process Equipment Shop Drawing Prep/Review/Approval
May 19, 2016
N/A
Process Equipment Fabrication / Delivery
October 6, 2016
NIA
Substantial Completion
October 31, 2016
Final Completion
November 30, 2016
Recommended Procurement and Installation Approach:
The following approach has been discussed with staff and is recommended:
i. Pre -Selection of the process equipment through a public bidding process. This
will allow for the process equipment to be released for fabrication while the
installation design is being finalized. Scope will include the aerator equipment
and the two large gates.
ii. Public bidding of the process equipment installation and associated electrical
work. The process equipment contract will be assigned to the successful prime
contractor to provide single point responsibility.
iii. The estimated professional services associated with the design and bidding of
this approach are $38,700.
SUPPORTING DOCUMENTS: ❑ ATTACHED X o NONE
POSSIBLE MOTION
Please word motion as you would like it to appear in the minutes.
1. Motion to direct AE2S to prepare public bid documents for the East WWTF Aerator process
equipment pre -procurement and advertise for bids.
2. Motion to direct AE25 to prepare public bid documents for the East WWTF Aerator general
construction and advertise for bids.
BUDGET INFORMATION
FUNDING:
WWTF Fund
ACTION TAKEN
BUDGETED: X ❑ YES
o NO
❑ APPROVED AS REQUESTED Q DENIED n TABLED ❑ OTHER (List changes)
COMMENTS: