Memorandum
City of Lawrence
Public Works Department
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TO: |
David L. Corliss, City Manager |
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FROM: |
Zachary D. Baker, Project Engineer |
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CC: |
Charles Soules, Mark Thiel, David Cronin |
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DATE: |
March 3, 2015 |
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RE: |
PW1135 6th and Iowa Reconstruction Change Order Approvals |
Background
Pursuant to the city/state agreement with the Kansas Department of Transportation (KDOT) for the turn back of 6th Street/US 40 from K-10 to Iowa, the state allocated $1,500,000 for geometric improvements at 6th and Iowa Streets. Additional scope changes including the 10 foot shared-use path on the north side of 6th Street and the extending of the RCB's under 6th Street caused the project cost to exceed the original budget. The project went to bid and the city received three (3) close bids under the engineer's estimate. At that time staff recommended issuing $500,000 in general obligation bonds to fund the balance and proceed with awarding the project to Bettis Asphalt. The commission approved that recommendation May 6, 2014.
Project Description
The primary scope of the 6th and Iowa project included constructing a dedicated left turn lane for west bound traffic. Sidewalk on the north side of 6th Street was reconstructed as a 10 foot shared-use path and the existing guard rails on both the north and south side of 6th Street were replaced with a combination of safety barrier and new guard rails. An eastbound right turn lane and new sidewalk on the south side of 6th Street to Rockledge was constructed. Pavement in the intersection was milled and overlaid and the Iowa approach was restriped to include dual left turns to westbound 6th Street. The traffic signal equipment was replaced with new black poles and includes LED street signs. All of this work and additional change orders was substantially completed by January 2015.
Change Orders
New construction items added to the scope and various constructability problems required an overrun of quantities. During the RCB extension, construction drainage issues were discovered that required additional storm sewer pipe and grading work. Constructability issues with guardrail installation required additional equipment and materials and increased costs. Modifications to a traffic signal pole was required when it was found that an adequate base could not be poured deep enough on top of the RCB at its planned location. Changes to that signal pole design required additional costs. It was decided that new decorative street lights were to be included with this project which increased costs. A faux finish was added to the corral rail barrier between 6th Street and the sidewalk to esthetically improve the intersection. Some curb modifications and asphalt patching was also needed during intersection construction. Areas between the proposed sidewalk and curb were filled with rock and exposed aggregate concrete in certain areas where it was deemed no grass would be able to grow. Finally additional guardrail repairs were needed, as shortly after construction of this project a vehicle accident destroyed a portion of the newly placed guardrail. These change orders and their costs are listed in the table below.
Final Construction Costs:
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Original PW1135 6th & Iowa Reconstruction Contract Bid |
$1,933,426.50 |
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Actual PW1135 Project Cost Before Change Orders |
$1,964,980.72 |
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Change Order 1 – Additional Storm Sewer & Grading Work |
$7,245.00 |
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Change Order 2 – Alternate Modified Guardrail Attachments |
$3,780.00 |
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Change Order 3 – Traffic Signal Equipment |
$6,362.00 |
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Change Order 4 – Street Light Equipment (9 Street Lights & 1 LED) |
$87,609.00 |
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Change Order 5 – Asphalt Wedge Patching |
$5,000.00 |
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Change Order 6 – Corral Rail, Add Faux Finish Paint to Street Side |
$4,200.00 |
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Change Order 7 – 30” Curb and Gutter with 12” Toe |
$2,000.00 |
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Change Order 8 – Clean Rock Installation Under Guardrail |
$2,715.75 |
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Change Order 9 – 6” Exposed Aggregate Concrete |
$9,525.00 |
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Change Order 10 – June Asphalt Material Index Adjustment ($561/ton - $538/ton=$23/ton, $1.00/ton increase) |
$43.00 |
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Change Order 11 – October Asphalt Material Index Adjustment ($605/ton - $538/ton=$67/ton, $3.00/ton increase) |
$3,112.62 |
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Change Order 12 – Remove Type II End Anchor & Replace w/ SKT Crashworthy Guardrail System |
$6,110.00 |
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Change Order 13 – Guardrail Repair – Southeast Corner 6th & Iowa |
$5,211.00 |
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TOTAL CHANGE ORDER COST |
$127,875.50 |
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TOTAL PROJECT COST |
$2,092,856.22 |
Staff Recommendation
The project was bid at $1,933,426.50 and is funded with $1,500,000 from the KDOT turn back agreement and $500,000 from GO bonds approved from Resolution No. 7071. Total change orders for this project were $127,875.50. Staff recommends funding $35,019.28 of the change order costs with remaining proceeds from the GO bonds approved by Resolution No. 7071. Staff recommends funding the remaining $92,856.22 of change order costs out of the infrastructure sales tax fund.
Action
Public works staff requests approval of Change Orders in the amount of $127,875.50.