Title
Proposed Change Order No. 1
Contract No. 2101255
Belle Isle Seawall Rehabilitation
CIP #116005 / BCE Score: 63.4
Body
Agenda of: October 25, 2023
Item No.: 2023-358
Amount: Original Amount $1,039,058.63
Proposed Change Order No. 1 1,119,186.77
Total Revised Contract $2,158,245.40
TO: The Honorable
Board of Directors
Great Lakes Water Authority
FROM: Suzanne R. Coffey, P.E.
Chief Executive Officer
Great Lakes Water Authority
DATE: September 29, 2023
RE: Proposed Change Order No. 1
Contract No. 2101255
Belle Isle Seawall Rehabilitation
Vendor: Dean Marine & Excavating, Inc.
MOTION
Upon recommendation of Cheryl Porter, Chief Operating Officer - Water and Field Services, the Board of Directors (Board) of the Great Lakes Water Authority (GLWA), authorizes the Chief Executive Officer (CEO) to enter into Contract No. 2101255, Proposed Change Order No. 1, “Belle Isle Seawall Rehabilitation” with Dean Marine & Excavating, Inc., at an increased cost of $1,119,186.77 for a total cost not to exceed $2,158,245.40 and an increased duration of 183 days for a total duration of 898 days; and authorizes the CEO to take such other action as may be necessary to accomplish the intent of this vote.
BACKGROUND
GLWA’s Belle Isle Intake was constructed in the early 1930s at the northeast tip of Belle Isle. It replaced a previously constructed (circa 1905) river intake. The Belle Isle Intake consists of a large manmade lagoon surrounded by earthen and stone dikes, an intake building with raw water instrumentation and debris bar racks, an emergency water inlet, and a chemical feed system for treating the intake and raw water tunnels for zebra mussels each year. The intake system serves three of GLWA’s five water treatment plants - Northeast, Springwells, and Water Works Park. The intake system is capable of supplying 940 million gallons per day (MGD), without boosting, to the three plants.
Contract No. 2101255 is a design-build contract that involves the design and construction of seawall and shoreline stabilization improvements at the head of GLWA’s Belle Isle Intake lagoon. Severe erosion has occurred along the shoreline over the past several years due to a failed seawall. The condition has been exacerbated by high water levels and, if left unabated, will cause additional damage to nearby structures such as a light beacon and other seawalls. The purpose of this project is to improve the seawall by engineering and installing a seawall that is designed to withstand the water levels that have recently been experienced as well as increase the coverage area of protection on the lagoon dike tip. Lastly, the project will restore a failed storm water collection system that is threatening to undermine the security fencing.
JUSTIFICATION
During the investigation portion of the project, it was discovered that the erosion at the tip of the intake lagoon was more extensive than what was known. The most concerning areas were located below the water surface. Without modifications to construction methods and increased engineering efforts, destabilization of the dike system and the navigation beacon caisson are real possibilities.
The seawall at the Belle Isle Intake is a critical part of the lagoon system formed by earthen and stone dikes. Without proper repairs and with continued erosion, the intake lagoon could become compromised. The possible impacts would be felt at three of GLWA’s five water treatment plants. The efforts required to restore the shoreline and integrity of the lagoon dike will result in decades of raw water resiliency.
PROJECT MANAGEMENT STATUS
Original Contract Time 715 days (10/10/2022 - 09/24/2024)
Proposed Change Order No. 1 183 days (09/25/2024 - 03/26/2025)
New Contract Time 898 days (10/10/2022 - 03/26/2025)
PROJECT ESTIMATE
Original Contract Price $1,039,058.63
Proposed Change Order No. 1 1,119,186.77
New Contract Total $2,158,245.40
FINANCIAL PLAN IMPACT
Summary: Sufficient funds are provided in the financial plan for this project.
Funding Source: Water Construction Fund
Cost Center: Water Engineering
Expense Type: Construction (5519-882111.000-616900-116005)
Estimated Cost by Year and Related Estimating Variance: See table below.
Original Contract Price $ 1,039,058.63
Proposed Change Order No. 1 1,119,186.77
New Contract Total 2,158,245.40
Financial Plan Estimate 1,039,000.00
Estimating Variance $ (1,119,245.40)
This negative estimating variance will be funded from Capital Reserves.
COMMITTEE REVIEW
This item was presented to the Operations and Resources Committee at its meeting on October 11, 2023. The Operations and Resources Committee unanimously recommended that the GLWA Board adopt the resolution as presented.
SHARED SERVICES IMPACT
This item does not impact the shared services agreement between GLWA and DWSD.