HomeMy WebLinkAboutA008 - October 28, 2025, Regular Meeting of the Ames City CouncilITEM #:11
DATE:10-28-25
DEPT:PW
SUBJECT:2021/22 STORMWATER DETENTION/RETENTION MAINTENANCE
PROGRAM - (NORTHRIDGE HEIGHTS POND)
COUNCIL ACTION FORM
BACKGROUND:
This annual program provides for long-term maintenance of stormwater detention facilities
within the City of Ames. These facilities provide regional stormwater detention and retention
across the community.
As a standard provision of developers' agreements, the City of Ames has responsibility
for the long-term maintenance of many of these facilities in residential areas. As these
facilities age, sediment accumulates, volunteer vegetation becomes more prevalent, erosion
occurs, and structures need to be improved. The program location for this project is the
Northridge Heights Pond.
On April 9, 2024, City Council awarded the contract to Tallgrass Land Stewardship Co., of
Waukee, Iowa in the amount of $111,600. To date, staff has administratively approved seven
change orders totaling $13,415. Change Order No. 8 (this Council action) in the amount of
$23,843.50 includes costs for the disposal of unsuitable materials, additional required
drainage pipe, and tied concrete block matting for erosion control. This change order
requires City Council approval because the change is over 20% of the original contract
value.
Additional project revenue is required to fund Change Order No 8. Staff has identified
$50,000 in project savings in the available Stormwater Utility Fund that can be utilized
to cover this expense.
Revenue and expenses associated with this program are as follows:
Funding Source Available Revenue Estimated Expenses
21/22 Stormwater Detention/Retention
(Stormwater Utility Fund)$150,000.00
Stormwater Utility Fund $ 50,000.00
Construction (As Bid) $ 111,600.00
Change Orders (previously approved by
staff) $ 13,415.00
Change Order 8 (this Council action) $ 23,843.50
Engineering/Administration (est.) $ 35,000.00
TOTAL $ 200,000.00 $ 183,858.50
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ALTERNATIVES:
1. Approve Change Order No. 8 to Tallgrass Land Stewardship Co., of Waukee, Iowa, in
the amount of $23,843.50 for the 2021/22 Stormwater Detention/Retention Maintenance
Program - (Northridge Heights Pond).
2. Direct staff to pursue changes to the project.
CITY MANAGER'S RECOMMENDED ACTION:
This change order is necessary to address site conditions and provide necessary
quantity adjustments to ensure proper project completion and compliance with design
requirements. Therefore, it is the recommendation of the City Manager that the City Council
adopt Alternative No. 1, as noted above.
ATTACHMENT(S):
Project Map.pdf
CO 8, Unsigned, 2021-22 Stormwater Facility Rehab (Northridge Heights).pdf
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KENNETH & MARIE MCCUSKEY
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ADS STORM SEWER
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APPROXIMATE AREA OF
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GRAPHIC SCALE
80'40'120'
Clapsaddle-Garber Associates, Inc
1523 S. Bell Ave. Suite 101
Ames, Iowa 50010
Ph 515-232-1784
www.cgaconsultants.com
SHEET NO.
DRAWN:
CHECKED:
DATE:
DATE:
APPROVED:DATE:
PROJECT NO.DESIGNED:DATE:REVISIONNO.DATEBY DATEBYREVISIONNO.
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CGA NORTHRIDGE HEIGHTS STORM WATER FACILITY REHAB
C.201
23-WR-0073
AMES, IOWA CONSTRUCTION BOUNDARY
JMG
JMG
MMB
TSM ----
----
----
----
CONSTRUCTION NOTES:
CONSTRUCTION ENTRANCE. TO BE RESTORED AFTER PROJECT
COMPLETION.
CONSTRUCTION LIMITS.
A
B
B
B
B
B
B
B
B
B
B
B
A
A
A
GENERAL NOTES:
ALL AREAS WITHIN CONSTRUCTION LIMITS SHALL BE RESTORED TO
ORIGINAL CONDITIONS OR BETTER.
THIS PROJECT IS LOCATED IN A HOMEOWNERS ASSOCIATION COMMON
PROPERTY. THE CONTRACTOR SHALL USE CAUTION TO NOT DISTURB
INDIVIDUAL HOMEOWNERS PROPERTY OUTSIDE OF THE PROJECT
LIMITS TO ENSURE THE SAFETY OF THE PUBLIC DURING
CONSTRUCTION.
CONSTRUCTION DETAILS
STABILIZED CONSTRUCTION ENTRANCEC.501
3
C.501
3
5.00'
35.00'
3
Date 21-Oct-25
CONTRACT CHANGE ORDER # 8 P.O.#63112
ACCT#Various
CONTRACTOR CHANGE ORDERS APPROVED TO DATE:
1 $3,700.00 11 PREVIOUS APPROVED
2 12 CHANGE ORDERS
3 $950.00 13 $13,415.00
ORIGINAL CONTRACT:
5 ($4,385.00)15 $111,600.00
CURRENT ADJUSTMENT
7 $9,100.00 17 $23,843.50
8 18 CUMULATIVE CHANGE
9 19 ORDER AMOUNT
10 20 $46,028.50
$22,185.00 ADJUSTED CONTRACT
$148,858.50
The contract is hereby modified and amended as follows:
ITEM DESCRIPTION UNIT PRICE QUANTITY TOTAL
Add 7 2" River Stone Ton $130.00 25.60 $3,328.00
It is mutually agreed that the contract price is increased/decreased by:Total:$23,843.50
0 days.
Contractor/Owner Date Municipal Engineer Date
Public Works Director Date City Manager Date
Page 1 of 1
For the City of Ames:
(Address)
Waukee, IA 50263
(City, State, Zip)
2021/22 Stormwater Facility Rehab (Northridge Heights)
Tallgrass Land Stewardship Co.
(Name)
PO Box 938
PROJECT:
CI TY OF AMES PUBLI C WORKS - ENGI NEERI NG DI VI SI ON
CC: Project Engineer, PW Mgmt. Asst., Finance, Contractor 10/21/2025 | 9:21 AM 4