Title: Replacement of 14 MG Reinforced Concrete Water Storage Reservoir and Pumping Station under a Golf Course: Planning, Design and Construction Challenges

Author(s): Ashok K. Dhingra

Publication: Symposium Paper

Volume: 285

Issue:

Appears on pages(s): 1-14

Keywords: Construction, Demolition, Design, Green, Management, Planning, Reinforced Concrete Reservoir, Seismic, Tank.

DOI: 10.14359/51683925

Date: 5/1/2012

Abstract:
This paper describes the planning, design and construction challenges to replace the existing, 80-year-old 14Million Gallons (54.81 Mega liters) Chevy Chase Reservoir and Pumping Station, located in Glendale, California. The existing and new reservoirs were/are fully buried, reinforced concrete structures under a golf course in Chevy Chase Country Club. The new reservoir was built on the footprint of the existing reservoir, on a tight site, involving shoring and stockpile of earth to be utilized for backfill following the completion of the reservoir. The location is in a residential neighborhood along a busy street. There was heavy community involvement and the concrete truck traffic on pour days as well as the rebar deliveries had to be carefully managed during construction. This paper discusses the planning, pre-design, design, constructability review and the construction management including the various QA/QC aspects throughout the project. The inclusion of special provisions for demolition of the existing facilities and other special conditions are addressed. The existing reservoir did not last the anticipated life of 100 years for a buried structure, the lessons learned and how the new ACI 350 code was implemented into the new reservoir design will be discussed. Also, the leakage testing requirements are described. Unforeseen subsurface conditions and unexpected contaminated perched groundwater along with the mitigation methods to improve soil and foundation conditions are discussed. The project was completed in record time, through an incentive clause in the contract documents. The project utilized the existing concrete material by crushing and using it as the sub base of the new reservoir, eliminating the need for hundreds of truck loads of material to be hauled offsite, contributing further to the Owner’s “Green Initiative” and reducing the overall carbon foot print. Several unique features and the overall performance of the project will also be addressed.