Third St. Overpass Retain WallMEMORANDUM
November 15, 2001
TO:
FROM:
SUBJECT:
The Honorable Mayor and City Council Members
Michael C. Van Milligen, City Manager
Retaining Wall Adjacent to Third Street Overpass
In December 1999, the City Council approved an agreement with Harborview
Developers for the construction of a new facility at the corner of Third and Main Streets.
As amended, this agreement includes the Developer managing some portions of the
public improvements to be made in the area. Assistant City Manager Cindy
Steinhauser and Public Works Director Mike Koch are recommending a further
amendment to construct a concrete retaining wall running east and west adjacent to the
Third Street Overpass at a proposed cost of $44,960.
I concur with the recommendation and respectfully request Mayor and City Council
approval.
MCVM/jh
Attachment
CC;
Michael C. Van Milligen
Barry Lindahl, Corporation Counsel
Cindy Steinhauser, Assistant City Manager
Michael A. Koch, Public Works Director
MEMORANDUM
November 13, 2001
TO:
FROM:
SUBJECT:
Michael C. Van Milligen, City Manager
Cindy Steinhauser, Assistant City Manager
Mike Koch, Public Works Director
Retaining Wall adjacent to Third Street overpass
Introduction
The purpose of this memorandum is to provide you information pertaining to the
construction of a retaining wall and sidewalk adjacent to the 3rd Street overpass and to
amend an existing contract for the completion of said improvements.
Background
In December 1999, the City Council approved an agreement with Harborview
Developers (Allen & Urbain) for the construction of a new facility at the corner of 3rd and
Main Streets. This Agreement was amended on August 14, 2000 to included Allen &
Urbain managing the public improvement portions of the site including the south
sidewalk plaza, retaining walls and sidewalk on the east elevation, historic light fixtures,
a brick fagade over the Main Street entrance into the new parking ramp and pedestrian
connections to the new parking ramp on the east side of the building. In January 13,
2001 this agreement was amended to include the construction of a retaining wall on the
north side of the building in response to concerns raised by the adjacent property owner
(Silver Dollar building). The combined cost of these improvements is approximately
$289,000.
Discussion.
In October, while reviewing drawings for the new parking facility, Conlon Construction
Company, the general contractor for the new parking ramp, raised concerns about the
grade elevations of the alley adjacent to the parking ramp and the Third Street
overpass. Specifically, the concerns were the depth of the cut that needed to be made
near the overpass (approximately 8' below grade) and the depth of the footings for the
overpass (approximately 2' below grade). In reviewing this matter with P.S. Vedi, the
architect for the new ramp, these concerns were considered valid and the assistance of
ilW Engineers was enlisted by the City to develop a retaining wall design that would
address any potential undermining of the overpass. Attached is the engineered drawing
by IIW Engineers, which has been reviewed and approved by IDOT.
This drawing identifies a poured concrete retaining wall that runs east-west adjacent to
the overpass and connects to a lower retaining wall constructed by Allen & Urbain as
part of the Chamber building construction. Based upon this information, it was
determined that an amendment of the existing contract with Allen & Urbain for the
construction of this retaining wall was the best course of action. This would provide for
seamless construction of both retaining walls by allowing us to proceed with the
construction utilizing their same contractor. The proposed cost of this improvement is
$44,960 or 15% of the current agreement with Allen & Urbain. This improvement will be
funded from the Parking Construction Fund balance, subject to a future budget
amendment to our current fiscal year. We have reviewed this information with
Corporation Counsel Barry Lindahl and he is in concurrence with our recommendation.
Request
The requested action is for the City Council to adopt the attached resolution, amending
the existing contract with Allen & Urbain for the construction of the proposed retaining
wall and sidewalk.
Cc:
Bill Baum, Economic Development Director
Tim Horsfield, Parking System Supervisor
RESOLUTION NO. 491-01
APPROVING AN AMENDMENT TO THE CONTRACT BETWEEN THE CITY
OF DUBUQUE AND ALLEN & URBAIN ASSOCIATES FOR THE CITY
OWNED IMPROVEMENTS FOR THE BUILDING ON THIRD & MAIN
STREETS.
Whereas, on August 14, 2000, the City Council approved a contract
between the City of Dubuque and Allen & Urbain for the management of the
public improvement portions of the building located at Third & Main Streets; and
Whereas, these improvements included the south sidewalk plaza,
retaining walls and sidewalk on the east elevation, historic light fixtures, a brick
fa(;ade over the Main Street entrance into the new parking ramp and pedestrian
connections to the new parking ramp on the east side of the building; and
Whereas, it is necessary to amend the contract to include the construction
of a retaining wall and sidewalk adjacent to the Third Street overpass.
NOW, THEREFORE, BE IT RESOLVED BY THE CITY COUNCIL OF
THE CITY OF DUBUQUE, IOWA:
Section 1. That the contract amendment attached hereto is hereby
approved.
Passed, approved and adopted this 19th day of November 2001.
/s/ Terrance M. Duggan, Mayor
Attest:
/s/ Jeanne F. Schneider, City Clerk
Additional Services Authorization
In accordance with the written agreement between Owner and Architect and the written
agreement between Owner and Construction Manager both dated as of August 14,
2000 between the parties designated below for design and construction management
services for relocated stone retaining walls, concrete retaining walls, driveways,
sidewalks, steps, ornamental rails, stone light base and lighting on Lots 1 and 3 of
Harbor View Place and amended on January 13, 2001 to include east retaining wall and
sidewalk.
The City of Dubuque hereby authorizes Allen & Urbain Architects and Construction
Managers to proceed with the following additional services:
Design of concrete retaining wall and sidewalk adjacent to Third Street
overpass.
Preparation of contract documents for the construction of said retaining wall
and sidewalk.
Soliciting bids for and/or negotiating construction contracts for the previously
listed work.
4. Managing and monitoring construction of the previously listed work.
Compensation for the services listed above shall be a Not-to-Exceed fee of:
Forty-four thousand nine hundred sixty dollars ($44,960)
Work outlined in this authorization is to begin upon receipt of the signed authorization
and is to be completed by December 15, 2001.
Theses services shall become a part of the agreements identified above and upon the
return of a signed authorization.
APPROVED BY:
Owner
City of Dubuque
50 West 13th St.
Dubuque, IA 52001
APPROVED BY:
Architect & Construction Mana.qer
Allen & Urbain Architects
And Construction Managers, Inc.
300 Main St., Suite 300
Dubuque, IA 52001
By: By:
Date: Date;
10/22/2001 09:56 FAX ~001
4155Pennsylvania Ave
Dubuque, lA 52002
Surveyors, P.C.
INTEGRITY.
EXPERTISE.
SOLUtiONS,
Voice: 563.556.2464
.~ngr.corn Fax: 563.556.7811
FAX Transmission
To: Paul Kalb
Company: Conlon Construction
From: Ron Baknez
Nmnber of pages (including cover sheet) 7
Date: 10/20/2001
Time: 12:33 PM
Project #: 99209-tl
Fax #: 582 4302
Message: 3rd Street Parking Ramp
Retaining wall system at south alley interface with Third Street Overpass Abutment.
V~'e have reverted back to the original cap slab concept to finish off the top of the wail.
~Ve decided to do this to provide better drainage characteristics off of the sidewalk to
the pavement below. This will serve to minimize icing on the sidewalk and water in the
backf'dl behind the walL We have only made a nominal connection between the top of
the wall and the un-reinforced sidewalk. The side~valk does not perform any structural
function.
Concrete:
Sidewalk - 4000 psi, %" LS aggregate, 5-7% air, broom finish perpendicular to
longitudinal slope. Wet cure 3 days. Rub formed surfaces.
Wall - 4000 psi, %' LS aggregate, 5-7% air, rubbed finish.
Footing - 3000 psi, 1" LS aggregate, 5-7% air.
Reinforcement- ASTM A615~ Grade 60.
Sealant - two-part urethane, Tremco Dymerie or equal. Ethafoam backer rod or bond
breaking tape. Seal sidewalk and wall control joints.
Excavate existing sand subgrade to profile shown without penetrating a 1:1 plane from
the toe of the existing MSE retaining wall mud sill. Backfill with native free draining
sand in 1'-0" lifts compacted with 2 passes of a vibratory plate. Hold vibratory plate 8
inches away from the back of the new retaining wall and the face of the existing MSE
retaining wall.
~--'-----~2~--'~'-~c~~p-~. ~ .4'2 ~ ~,,~' ~4'.g.~ W~' '~" '"~' ~ ........
John ~len, 556 4394 . -& ~ . ~.
10/22/2001 09:67 FAX ~002
M
10/22/2001 09:58 F3~K ~003
3rd Street Ramp/Bridge Abutment Retaining Wall Schedule
mark
pour top of wall segment top of toe of
sequence segment west length footing footing
key depth
wall reinf.
dowels
dowel
proj.
A 3 620.16 5'-0" 614.5' 6'-0" 1'-6" #6@9" 36"
B 2 619.08 5L0'' 614,25' 8'-0" 1'-6" #6@9" 36"
C 1 619.41 5'-0" 613.75' 5'-6" 1'-6" #6@9" 36"
D 3 619.04 5'-0" 613.5' 5'-6" I'-6" #5@9" 30"
E 2 618.67 5'-0" 613.5' 5'-6" 1'-6" #5@9" 30"
F 1 618.28 5'-0" 613.5' 5'-0" 1'-6" #5@9" 30"
G 3 617.91 10'-0" 613.25' 4'-6" 1'-0" #5@12" 30"
H 2 617.15 10'-0" 613.0' 3'-6" 0'-8" #5@12" 30"
J 1 616.4 10L0" 612.75' 2'-0" 0'-4" #5@12" 30"
K 3 615.65 10'-0" 612.25' 2'-0" 0'-4" ¢~@12" 24"
L 2 614.9 t0'-0" 611.75' 2'-0" 0'-4" ¢4@12" 24"
M 1 614.t5 10'-0" 6II.25' 2'-0" 0 ¢~4@12" 24"
N 3 613.39 12'-0" 610.75' 2'-0"
P 2 612.49 to end (12'+/-) 610.25' 2'-0"
24"
10/22/2001 09:59 FAX ~005
10/22/2001 09:59 FAX ~006
10/22/2001 10:0i F~X ~007