Report to Mayor and City Council
Tuesday, July 16, 2024
Consent
SUBJECT:
Title
CONSIDER ACCEPTANCE OF THE WORK COMPLETED BY OHL USA, INC. FOR PROJECT NO.1515: CARRIAGE CREST STORMWATER FACILITY (CITY COUNCIL)
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I. SUMMARY
On May 16, 2018, the City entered into a Construction Contract with OHL USA, Inc., the lowest responsible bidder, for an amount not to exceed $11,198,500.00 for the completion of Project No. 1515 - Carriage Crest Stormwater Facility. The City Council also authorized the expenditure of a 15% construction contingency in an amount not to exceed $1,679,775.00 for change orders such as the removal and remediation of contaminated soil, substructure conflicts, and other unforeseen construction work that may be required to complete this project.
The project has been constructed in accordance with the approved plans and specifications. It is requested that City Council accept the work as completed to allow the designer, Los Angeles County Sanitation District to perform the necessary repair to the mechanical equipment to make it fully operational.
The City and Los Angeles County Sanitation District (LACSD) entered into a Stormwater Project Services Agreement dated July 19, 2016, where LACSD was retained to provide support, planning, design, and construction management services under the agreement to assist the City with the completion of the Project. Tetra Tech, Inc. is LACSD’s subconsultant for the design component.
LACSD is scheduled to utilize County resources to bring the project to operational status. The City and LA County plan to have the plant operational in time to meet the next winter rainy season.
II. RECOMMENDATION
Recommendation
Take the following actions:
1. ACCEPT the work completed by OHL USA, Inc. for Project No.1515, Carriage Crest Stormwater Capture facility project and suspend the remaining work for convenience.
2. AUTHORIZE LACSD to perform the remaining work to complete Project 1515: Carriage Crest Stormwater Capture Facility.
1.
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III. ALTERNATIVES
1. DO NOT ACCEPT the completed work by OHL, Inc. However, this will delay LACSD from mobilizing their resources to make the design changes to fully commission the project.
2. TAKE another action the City Council deems appropriate and consistent with the requirements of the Law.
IV. BACKGROUND
The City is subject to extensive requirements to improve stormwater quality through its MS4 Permit, and Project No. 1515 - Carriage Crest Park Stormwater Capture Facility (Project No. 1515) will greatly advance the City’s compliance efforts. The City participates in the regional Enhanced Watershed Management Program (EWMP) to address the associated permit requirements, and Project No. 1515 was identified in the EWMP for the Dominguez Channel Watershed Management Area Group as a high priority for improving the water quality that drains to the Dominguez Channel, Machado Lake, and the Los Angeles River.
The project consists of the pretreatment of stormwater from an existing storm drain system, the diversion of the stormwater to a subsurface storage reservoir, and ultimately discharge to the sanitary sewer for treatment at the LACSD Joint Water Pollution Control Plant (JWPCP) for reclamation. This project will address and/or prevent surface water quality issues, provide reclaimed water for irrigation, and enhance groundwater supplies.
On May 16, 2018, the City entered into a Construction Contract with OHL USA, Inc., the lowest responsible bidder, for an amount not to exceed $11,198,500.00 (Exhibit No. 1). The City Council also authorized the expenditure of a 15% construction contingency in an amount not to exceed $1,679,775.00 for change orders such as the removal and remediation of contaminated soil, substructure conflicts, and other unforeseen construction work that may be required to complete this project.
The construction has faced several challenges, and the project completion has been significantly delayed. The construction challenges included:
• Rain delays occurring primarily in the winter of 2018/2019.
• Delays associated with the contractor’s design and implementation of the shoring system associated with the main excavation.
- Shoring wall deflection due to the movement and significant surface cracks observed at multiple locations.
• Characterization and management of contaminated soil.
- Contaminated soils at various areas outside of the footprint of the storage units which required additional handling, sampling, testing, and disposal of chemically impacted soil.
• Issues with the installation of the storm trap units related to the protection of the impervious liner and grading.
• Various contractor related productivity issues.
LACSD has been retained by the city to provide support, planning, design and construction management services per agreement dated July 19, 2016. Tetra Tech is LACSD’s sub consultant that completed the design plans. The work has been completed by OHL USA, Inc. per approved design plans. However, it was determined that the finished design grade of the baseball field is creating rainwater intrusion into the mechanical vault which resulted in damage of the newly installed actuators and sensors. LACSD is committed to perform the necessary repairs and is ready to mobilize their resources to finalize the project and bring it to operational status. The LACSD is slated to commence their work in September 2024.
The design changes that need to be made to fully commission the project include grading, replacement of actuators and sensors, new drop inlets for drainage and irrigation for the area that is being graded to avoid water intrusion into the vaults.
V. FISCAL IMPACT
The Los Angeles County Sanitation District will be responsible for the cost of the repair to make the facility fully functional. The repair needed will have no impact to the city’s General Fund.
VI. EXHIBITS
1. Contract Agreement with OHL (pgs. 4-60)
Prepared by: Dr. Arlington Rodgers,Jr., Director of Public Works, Gilbert Marquez, P.E., City Engineer and Kenneth Young, Senior Civil Engineer.