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Date
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December 4, 2006
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Agenda
Item No. 8 Roll
Call No. 06- Communication No. 06-752 Submitted by: Jeb E.
Brewer, P.E. City Engineer and William G. Stowe Assistant City Manager/Public
Works/Engineering |
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AGENDA
HEADING:
Approving and
authorizing the execution of Iowa Department of Transportation (Iowa DOT)
Change Order No. 7 to Keo Way Phase 2 Storm Sewer Outlet not to exceed City
cost of $138,831.06.
SYNOPSIS:
Recommend approval of Change Order No. 7 as prepared by the Iowa DOT not to exceed $241,026.16, with the City share being $138,831.06, for the cost to continue work on the 10-foot x 5-foot reinforced concrete box (RCB) storm sewer to the end of the project, and complete the connection to the existing 10-foot x 5-foot RCB storm sewer, along with suitable backfill and pavement during winter construction.
FISCAL
IMPACT:
Amount:
$138,831.06
Funding
Source: 2006-2007 CIP, Page Street-23, I-235 Storm
and Sanitary Sewer Improvements, STR197, Storm Sewer Utility Funds
Amount:
$102,195.10
Funding
Source: Iowa Department of Transportation State
Funds
ADDITIONAL
INFORMATION:
On May 22, 2006,
under Roll Call No. 06-977, the City Council approved a preconstruction
agreement with Iowa DOT for Keo Way (Birds Run) Phase 2 Storm Sewer related to
I-235, where the City will reimburse Iowa DOT an estimated 57% of the storm
sewer cost, 100% for any enhanced storm capacity, and 100% of sanitary sewer
cost. The repayment will begin in FY
2007-08. As part of this agreement,
change orders exceeding $25,000 in additional City contribution must be
approved by the Des Moines City Council.
On August 7,
2006, under Roll Call No. 06-1555, the City Council approved Change Order No. 2
in the amount not to exceed $374,149.58, City share being $124,716.53, for
boring 40 lineal feet of 54-inch sanitary sewer with casing and 84 lineal feet
of 10 ft. x 5 ft. reinforced concrete box storm (RCB) sewer underneath the
Qwest communication utilities. This
change order work was beneficial to Qwest as it eliminated their cost to
relocate the duct, beneficial to the Iowa DOT in order to keep traffic phasing
on schedule, and beneficial to the City in order to minimize downtown access
disruptions. All three parties agreed
to share the $374,149.58 cost equally.
Change Order No. 2 work required jacking the 10-foot x 5-foot RCB storm sewer and 54” sanitary sewer pipe under the Qwest duct banks that cross Keo Way, and required 10 weeks to complete. This was longer than originally estimated due to the poor condition of the duct bank. This delay forces work on the remainder of the project to be extended to the spring of 2007. However, the 10-foot x 5-foot RCB storm sewer must be connected to the existing 10-foot x 5-foot RCB storm sewer outlet at the north end of Keo Way before spring. Without the 10-foot x 5-foot RCB storm sewer being connected to the outlet, significant flooding could occur along Keo Way during spring rainfall events.
In order to connect the 10-foot x 5-foot RCB storm sewer to the outlet, the project will need to continue through the winter months. As the hot mix asphalt (HMA) plants will close for the season, the pavement replacement will be 10” Portland cement concrete (PCC) placed in winter conditions with 2” HMA overlay in the spring. With winter conditions, there will be additional cost of heated water for the PCC pavement, subgrade, and pavement protection. Also, there will be unsuitable material for backfill due to winter conditions. The unsuitable material will be hauled for disposal and replaced with recycled HMA. The total change order cost is $241,026.16, with the City’s share being $138,831.06.
Discussions will be held with Qwest to determine their participation with this change order, similar to Change Order No. 2 where Qwest contributed 1/3 of the cost. Any funds contributed by Qwest will be applied to the City and IOWA DOT cost share percentages proportionately.
PREVIOUS
COUNCIL ACTION(S):
Date: August
7, 2006
Roll
Call Number: 06-1555
Action: Approving
and authorizing execution of Iowa Department of Transportation Change Order No.
2 to Keo Way Phase 2 Storm Sewer Outlet, not to exceed $124,716.53. (Council
Communication No. 06-501) Moved
by Vlassis to adopt. Motion Carried
6-1.
Date: May
22, 2006
Roll
Call Number: 06-977
Action: Authorizing
execution of Iowa Department of Transportation Preconstruction Agreement for
Keo Way (Birds Run) Phase 2 Storm Sewer Outlet. (Council
Communication No. 06-294) Moved by Vlassis to adopt. Motion Carried 7-0
Date: August
31, 2000
Roll
Call Number: 00-3634
Action: Approving Iowa Department of Transportation
Predesign Agreement for Interstate 235, from the west City limits to the north
City limits. (Council
Communication No. 00-411). Moved by McPherson to adopt. Motion Carried 4-2-1. Nays: Brooks and Vlassis. Absent: Flagg
BOARD/COMMISSION
ACTION(S): NONE
ANTICIPATED
ACTIONS AND FUTURE COMMITMENTS: NONE