HomeMy WebLinkAbout2025-08-04 I01D_01 Professional Consulting Services Agreement Amend 1_NW 6th St Culvert Over Little Walnut CreekAGENDA ITEM:
CITY OF WAUKEE, IOWA
CITY COUNCIL MEETING COMMUNICATION
MEETING DATE: August 4, 2025
AGENDA ITEM:Consideration of approval of a resolution approving Engineering Services
Amendment No. 1 with Foth Infrastructure and Environment, LLC [NW 6th
Street RCB Culvert Over Little Walnut Creek]
FORMAT:Resolution
SYNOPSIS INCLUDING PRO & CON: The original Professional Consulting Services Agreement
(PCSA) for the NW 6th Street RCB Culvert Over Little Walnut Creek Project with Foth was approved
on February 22, 2022 (RES# 2022-063) for the amount of $100,000. Foth Infrastructure and
Environment, LLC., has requested Amendment No. 1 in the amount of $115,000 to compensate Foth
for services provided during the final design phase of the project. The original CIP scope estimated a
single barrel 12' x 10' reinforced concrete box culvert. After engaging the Iowa DNR and FEMA to
permit the project within the floodway, the hydraulic model received from FEMA indicated a triple
barrel 12' x 10' culvert was necessary, with an estimated cost of $900K. Foth updated the hydraulic
model to reflect field survey data and ran updated model scenarios, of which indicated a triple barrel
culvert was grossly oversized. In order for the City to contest the triple barrel culvert sizing, a
Condition Letter of Map Revision (CLOMR) review through FEMA was necessary to prove a smaller
culvert would work without negative flooding impacts to adjacent public infrastructure and private
property. The CLOMR hydraulic modeling efforts indicated a twin barrel 10' x 10' culvert would
work and after several back and forth exchanges with FEMA, they issued the CLOMR. The twin
barrel 10' x 10' culvert has an estimated cost of $600K, resulting in a net savings of approximately
$200K after compensating Foth for the amendment 1 costs. Total project cost is currently estimated at
$1.41M.
FISCAL IMPACT INCLUDING COST/BENEFIT ANALYSIS: The Agreement will be amended
to the amount Not to Exceed $215,000.00
COMMISSION/BOARD/COMMITTEE COMMENT:
STAFF REVIEW AND COMMENT:
RECOMMENDATION: Approve the resolution.
ATTACHMENTS: I. Resolution
II. Agreement for Professional Consulting Services Amendment No. 1
PREPARED BY: Lisa Bauman
REVIEWED BY: Rudy Koester RK
I1D1
THE CITY OF WAUKEE, IOWA
RESOLUTION 2025-
APPROVING ENGINEERING SERVICES AMENDMENT NO. 1 WITH FOTH
INFRASTRUCTURE AND ENVIRONMENT, LLC.,
[NW 6TH STREET RCB CULVERT OVER LITTLE WALNUT CREEK PROJECT]
IN THE NAME AND BY THE AUTHORITY OF THE CITY OF WAUKEE, IOWA
WHEREAS, the City of Waukee, Iowa is a duly organized municipality within Dallas County;
AND,
WHEREAS, on February 2, 2022 (Resolution #2022-063), the Waukee City Council approved
an agreement with Foth Infrastructure & Environment LLC for the NW 6th Street RCB Culvert
Over Little Walnut Creek Project; AND,
WHEREAS, Amendment No. 1 is necessary to compensate Foth for Conditional Letter of Map
Revisions (CLOMR) and Floodplain Revision Services provided during the final design phase of
the project.
NOW THEREFORE BE IT RESOLVED by the City of Waukee City Council in session this
4th day of August, 2025, that it hereby approves the Engineering Services Amendment No. 1
with Foth Infrastructure and Environment, LLC [NW 6th Street RCB Culvert Over Little Walnut
Creek Drive].
____________________________
Courtney Clarke, Mayor
Attest:
___________________________________
Rebecca D. Schuett, City Clerk
RESULTS OF VOTE: AYE NAY ABSENT ABSTAIN
R. Charles Bottenberg
Chris Crone
Rob Grove
Anna Bergman Pierce
Ben Sinclair
Foth Infrastructure and Environment, LLC NW 6th Street RCB Culvert Over Little Walnut Creek
Project Number 22W003.01 Waukee, Iowa
Page 1
ENGINEERING SERVICES AMENDMENT NO. 1
WAUKEE CITY PROJECT NO. _________________
THIS AMENDMENT, made and entered into this 4th day of August, 2025 by and between, the CITY OF
WAUKEE, IOWA, hereinafter referred to as the “City”, and FOTH INFRASTRUCTURE AND ENVIRONMENT,
LLC., hereinafter referred to as the "Consultant", for professional services in connection with FEMA MT-2
submittal for CLOMR & Floodplain Revisions for the NW 6th Street RCB Culvert Over Little Walnut Creek
Project in Waukee, Iowa, hereby amends the original Agreement dated February 22, 2022, to include
additional services associated with the following tasks:
I. BASIC SERVICES OF THE CONSULTANT
The CONSULTANT shall consult on a regular basis with the CITY to clarify and define the City’s
requirements for the Project and review available data. The CITY agrees to furnish to the
CONSULTANT full information with respect to the CITY’s requirements, including any special or
extraordinary considerations for the Project or special services needed, and also to make available
pertinent existing data. The CONSULTANT shall provide the following basic services in regard to the
Project:
A. PROJECT COORDINATION
CONSULTANT shall coordinate and attend meetings with Civil Design Advantage (developer’s
engineer), Iowa DNR, and FEMA (Federal Emergency Management Agency) to provide a brief
overview of the proposed improvements as well as project goals and objectives. The meeting(s) will
include exhibits and an active discussion to address any concerns and comments. This task also
includes any follow-up meetings to address comments during the FEMA review process. For
estimating purposes, it assumed a total of six (6) coordination meetings will be held.
B. DESIGN SURVEY
CONSULTANT will perform field and office tasks required to collect additional topographic
information deemed necessary to complete the CLOMR (Conditional Letter of Map Revision)
Submittal. The specific supplemental survey tasks to be performed include the following:
1. LiDAR Survey – Download and process .pod files of the Little Walnut Creek watershed
and associated tributaries.
2. Project Base Map – Incorporate field surveys and LiDAR data into an electronic base map
to be used for the design of the project. Incorporate property lines, right-of-way lines, and
property ownership for parcels located within the project limits of the base map.
C. LEGAL SURVEY
CONSULTANT shall prepare easement plats and legal documents for property needed for permanent
and construction easements for the project. For estimating purposes, it is assumed that one (1) plat
for permanent easement and one (1) plat for temporary construction easement will be needed for this
project. The CONSULTANT shall coordinate with the CITY for any remaining Real Estate Service
required for the project.
Individual plats and legal descriptions will be prepared for each parcel. The legal descriptions shall be
“of” descriptions and not metes & bounds descriptions. The plats and legal descriptions shall comply
with requirements of the Iowa Code and shall be prepared by or under direct supervision of duly
licensed surveyor under the laws of the State of Iowa. The plats shall also be completed in
accordance with the City of Waukee requirements.
Foth Infrastructure and Environment, LLC NW 6th Street RCB Culvert Over Little Walnut Creek
Project Number 22W003.01 Waukee, Iowa
Page 2
D. HYDROLOGIC MODELING
CONSULTANT will complete a study of the drainage basin of Little Walnut Creek, upstream of Warrior
Lane, to develop a hydrologic model of Little Walnut Creek. USDA’s WinTR-55 small watershed
program will be utilized to generate the hydrologic model. The model will include the following:
1. TASK 1 – Drainage Basin Identification
Delineate the existing drainage basin/sub-basin areas using existing LiDAR data to
supplement field survey. The task includes completing limited field investigations to
validate and resolve discrepancies in existing information. The drainage basins
established in this task will be incorporated into modeling the reach of Little Walnut
Creek.
2. TASK 2 – Drainage Model
Develop a hydrological model of the overall drainage basin and analyze the discharge
flows for 5-yr, 10-yr, 25-yr, 50-yr, 100-yr, and 500-yr flood events. Land use details, time of
concentration paths, and reach data will be gathered from existing aerial and topographic
maps. Storm data used in the model will be acquired from NOAA Point Precipitation
Frequency Estimates. Model will be compared to the existing published FIS flows and
calibrated to ensure accuracy.
E. HYDRAULIC MODELING
Four (4) HEC-RAS models with natural and floodway (encroached) runs will be developed for the
CLOMR submittal. All elevations in the hydraulic model reference the NAVD88 datum.
1. TASK 1 – Duplicate Effective Model
CONSULTANT will acquire existing hydraulic model for Little Walnut Creek (LWC) from
FEMA in HEC-2 format and convert said model to HEC-RAS format.
2. TASK 2 – Corrective Effective Model
Due to the age of the existing model, CONSULTANT will add surveyed cross sections
near the NW 6th Street project area into the hydraulic model. Errors and notes when
running the model will be corrected and compared to the model output and published
maps to ensure accuracy and legitimacy.
3. TASK 3 – Existing/Pre-Project Conditions Model
Corrective effective model will be truncated to the area located at and upstream of the
NW 6th Street Culvert Crossing (River Sta. 37442 to 27904). Known water surface
elevation taken from the corrective effective model at River Sta. 27904 and inputted as
the Reach Boundary Condition for the Steady Flow Data.
4. TASK 4 – Post-Project Conditions Model
Calculated flows developed with the hydrologic model will be inputted for Little Walnut
Creek upstream of NW 6th Street while the published FIS flows will be used for the
remaining reach downstream. The proposed culvert for NW 6th Street will also be added
to the model with proposed channel and bank shaping around the culvert.
A Hydrologic and Hydraulic Technical Memorandum will be prepared to document the analysis of the
overall Little Walnut Creek watershed. The report will document the drainage area boundaries, land
use details, comparison to published FIS, and summary of hydraulic analysis.
F. FEMA CLOMR SUBMITTAL
CONSULTANT shall coordinate with the CITY, Iowa DNR, and FEMA for the preparation and submittal of a
CLOMR as well as modifications to existing Flood Insurance Rate Maps (FIRMs).
Foth Infrastructure and Environment, LLC NW 6th Street RCB Culvert Over Little Walnut Creek
Project Number 22W003.01 Waukee, Iowa
Page 3
CONSULTANT will prepare exhibits and supporting documents for submittal to FEMA for review of
proposed floodplain changes to Little Walnut Creek. CONSULTANT will include:
1. A written description of the purpose of the MT-2 request and the scope of the proposed
project along with the methodology used to analyze the projects effects.
2. Files in digital format of all HEC-RAS models used for Hydraulic Analysis and WinTR-55
models used for Hydrologic Analysis. This includes associated backup information and
calculations used in the analyses.
3. Digital format (CAD or GIS) of a certified topographic work map that encompasses the
limits of the floodway and floodplain change.
4. Proposed plans, certified by a registered Professional Engineer, for all project elements.
5. A floodway public notice certifying that the City has notified all affected property owners,
in compliance with NFIP regulations Subparagraph 65.7(b)(1).
6. A copy of the individual legal notices sent to all property owners affected by any changes
in the flood hazard information.
7. A copy of the Threatened & Endangered Species Assessment to show compliance with
the Endangered Species Act (ESA).
The CONSULTANT assumes completed MT-2 Application will include only Form 1, Form 2, and Form
3 for FEMA review. Revisions are expected to be completed by CLOMR.
G. FEMA REVIEW FEES
Fees will include FEMA review of “CLOMR Based on Bridge, Culvert, Channel, Hydrology, or
Combination Thereof” ($6,500.00). Fees will be paid with a receipt provided for invoicing.
In consideration of these services, the CITY agrees to increase the compensation for services performed by
the CONSULTANT. These fees are based on the current standard hourly rates of the CONSULTANT’S
personnel actually engaged in the performance of the services, plus direct out-of-pocket costs for expenses
incurred by personnel who are actually engaged in the work and other direct costs. The total Hourly Not-to-
Exceed fees for the professional engineering services as described in this amendment are as follows:
I. Basic Services of the Consultant
A. Project Coordination $15,000.00
B. Design Survey $6,000.00
C. Legal Survey $5,500.00
D. Hydrologic Modeling $30,000.00
E. Hydraulic Modeling $40,000.00
F. FEMA CLOMR Submittal $12,000.00
G. Fee to FEMA for Review $6,500.00
Total $115,000.00
THIS AMENDMENT is subject to all provisions of the original Agreement.
Foth Infrastructure and Environment, LLC NW 6th Street RCB Culvert Over Little Walnut Creek
Project Number 22W003.01 Waukee, Iowa
Page 4
THIS AMENDMENT, together with the original Agreement represents the entire and integrated
AGREEMENT between the CITY and CONSULTANT.
THIS AMENDMENT executed the day and year written above.
FOTH INFRASTRUCTURE AND ENVIRONMENT, LLC. CITY OF WAUKEE, IOWA
By: By: _______________________________________
Joshua C. DeBower, Senior Client Team Leader
WITNESS ATTEST
By: By: _______________________________________
Patrick P. Kueter, Director
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