HomeMy WebLinkAboutA041 - Resolution approving Change Order No. 10 with Woodruff Construction for Water Pollution Control Facility Nutrient Reduction Modifications Phase 1 ProjectITEM #:42
DATE:07-14-26
DEPT:W&PC
SUBJECT:WATER POLLUTION CONTROL FACILITY NUTRIENT REDUCTION
MODIFICATIONS PHASE 1 PROJECT - CHANGE ORDER #10
COUNCIL ACTION FORM
BACKGROUND:
On August 13, 2024, City Council awarded a contract to Woodruff Construction for
modifications to the Water Pollution Control Facility (WPCF) in the amount of $53,370,000.
These modifications are the first of two construction phases that will ultimately enable the
facility to achieve the goals of the Iowa Nutrient Reduction Strategy.
As is common with large construction contracts, this project has required multiple change
orders. To date, nine change orders have been approved for a combined total reduction in the
contract price of $72,011.36. Details regarding the scope and amounts of each change order
are outlined below in Table 1.
A tenth change order has been prepared and is ready for Council approval. The largest
single item ($231,618.27) is to replace all six variable frequency drives (VFD's) in the
Raw Water Pump Station (RWPS). The VFD's allow the speed of the pumps to be varied to
more closely match the rate of flow entering the Water Pollution Control Facility. This avoids
having frequent pump starts and stops and allows for a more consistent flow rate through the
facility and a more uniform treatment effectiveness.
The existing drives have already exceeded their anticipated 15-year useful life. One of the
drives has failed, and several others are in need of extensive repairs. Because these VFD's
serve the raw wastewater pumps, the facility's first and most critical pumping process,
replacing them now reduces the risk of future failures and improves the long-term
reliability of the treatment plant. City staff requested that Woodruff, the general
contractor, prepare a cost proposal for replacing these VFD's.
There are advantages to completing this work as part of the current project rather than
under a separate future contract. In addition to having the contractor and electrical
subcontractor already mobilized and familiar with the facility, the new VFD's will use
the same Allen-Bradley controls platform, programming approach, enclosure design,
documentation standards, and control components being provided elsewhere in the
Nutrient Reduction project. This provides greater consistency for operations and
maintenance staff and simplifies future troubleshooting, maintenance, and spare parts
management.
To ensure that the City was receiving a fair, competitive cost proposal, staff requested
the design engineer, Strand Associates, to evaluate the pricing. Even prior to receiving
the proposal from the contractor, Strand prepared their own budget estimate range.
Woodruff's proposal fell within the middle of that range. Strand also obtained
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independent pricing from another manufacturer's representative and received pricing
similar to Woodruff's costs. Based on that evaluation, staff believe that the change
order pricing provided by Woodruff is fair and reasonable for the equipment and scope
being provided.
Other minor changes includes in this change order are to add additional structural load
transfer plates in the Raw Water Pump Station ($2,902.25), substitute galvanized steel
expansion joint hardware in lieu of stainless steel (credit of $3,600), and a no-cost correction
from Change Order No 9 where a subtotal was shown with two digits transposed (the total
amount of the Change Order 9 was correct, and this does not adjust the overall contract
amount).
Table 1: Change Order Summary
Change Order #1
Credit for Enviromix, fire alarms, canopy; reroute gate power circuit; expansion
joint changes.
(231,878.79)
Change Order #2
Modifications to the ceiling and lighting in portions of the Administration Building.(25,280.00)
Change Order #3
Changes to Control Box A & B; changes to framing elements, reimbursement for
special inspections.
10,835.86
Change Order #4
Changes to door framing; changes to ceiling tiles; changes to electrical outlets;
additional painting requested by staff.
13,459.25
Change Order #5
Changes to valves & piping in Structure 10; changes to reinforcing and electrical
at Structure 20; add booster fan; casework changes in admin building; add (2)
well supply tanks and well control modifications; Deletion of gate valve in Control
Box A (later restored as part of Change Order #9); misc changes in Structure 20.
(40,743.03)
Change Order #6
Integrate doors into fire alarm in Admin; change paving to PCC for (8) parking
stalls; credit for brass tags vs stainless; credit for rehab slide gate valves in
Structure 10 versus replacement; Structure 200 berm elevation changes; corner
guards in Structure 200; changes to the 4" DCW line near the RWPs.
$71,844.57
Change Order #7
Add asbestos and lead abatement for demolition of old admin building; add
remote control for trolley hoist; misc electrical changes; add door holder/closer;
extend water line in grit building; additional fencing; removal of unknown
foundation under old admin building; add additional wireless access points.
$44,527.37
Change Order #8
Relocate overhead door; door hardware change; credit from water line
relocation; door opener to Room 20012; add corner guards in admin building;
substitute PLC type.
$3,843.61
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Change Order #9 - this action
Credit for eliminating crimp connectors; install water supply, drain, and install
owner-supplied sink in shop; credit for eliminating hangers on energy recovery
unit duct; remove and replace gate door in Control Box A.
$81,379.80
Change order #10 - this action
Supply and install (6) new VFDs for the Raw Wastewater Pumps, add (4)
load transfer plates, credit for expansion joint material change, no-cost
correction to Change Order #9.
$230,920.52
Total Approved Change Orders (Including this action)
Percent of Original Contract
$158,909.16
0.30%
Table 2 below summarizes the overall project budget, including the $500,000 grant that was
received earlier this year.
Table 2: Total Project Funding & Expenses
Funding Expenses
Prior Years
FY 2023 1,000,472.42
FY 2024 1,438,643.35
FY 2025 Adjusted 26,610,884
FY 2026 26,240,000
FY 2027 7,250,000
WTFAP Grant - Iowa Finance Authority 500,000
Engineering
6,038,000
Construction
Original Contract 53,370,000
Change Order #1 (231,878)
Change Order #2 (25,280)
Change Order #3 10,836
Change Order #4 13,459
Change Order #5 (40,743)
Change Order #6 71,845
Change Order #7 44,527
Change Order #8 3,844
Change Order #9 81,380
Change Order #10 - This Action 230,921
Owner Allowance (furnishings, etc.) 400,000
All Other Expenses 122,675
TOTAL 63,040,000 60,089,586
Available Contingency 2,950,414
The Clean Water State Revolving Fund (CWSRF) loan was approved in a not-to-exceed
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amount of $65,185,000 to provide a cushion for unanticipated project changes and prevent
unnecessary issuance costs associated with increasing the not-to-exceed amount as a
separate action, should it be necessary.
It should be noted that the SRF program is a reimbursement program, meaning that the City
first spends the money, then the program reimburses for eligible expenses. This method
ensures the City will only borrow for expenses the City Council has authorized and are
necessary to complete the project, thus minimizing interest expense associated with the
improvements.
ALTERNATIVES:
1. Approve Change Order #10 to the contract with Woodruff Construction for the Water
Pollution Control Facility Nutrient Reduction Modifications Phase 1 Project in the amount
of $230,920.52.
2. Approve the change order minus the VFD replacements. It would leave one VFD in it's
failed condition and leave others approaching failure. The VFD replacements could be
scheduled in a future year CIP, but likely at a higher cost if done as a stand-alone
project.
3. Do not approve the change order. This would reject the recommended changes to the
contract documents.
CITY MANAGER'S RECOMMENDED ACTION:
The proposed changes are to maintain and improve the reliability and function of the
Water Pollution Control Plant Modifications. The consultant, contractor, and City staff
have worked closely together to come up with reasonable, cost-effective
recommendations. Therefore, it is the recommendation of the City Manager that the City
Council adopt Alternative 1 as described above.
Council should be aware that the VFD replacement would draw down the
unencumbered contingency on the project. However, there would still be nearly $3
million in available contingency funds for the balance of the contract.
ATTACHMENT(S):
CO10&Encl. _to Owner.pdf
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