HomeMy WebLinkAbout03. CC 686B Approve Plans & Specs Groundwater Wells No. 27 and 28 - Auth to BidM
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FROM: OFFICE OF THE CITY MANAGER
BY: DELFINO R. CONSUNJI, P.E., DIRECTOR OF PUBLIC O ISS/CI NGI R
DATE: AUGUST 28, 2018
That the City Council approve the plans and specifications and authorize solicitation for bids for
Groundwater Wells No. 27 and 28 Drilling, Construction, Development, and Testing, Cash
Contract No. 686B.
The City relies on groundwater from aquifers within the Central Groundwater Basin to meet
100% of the potable water demands of its customers. To help ensure a reliable and cost-
effective supply of drinking water into the future and to maintain independence from more
expensive and less reliable imported water, the City is proposing the installation of two new
deep groundwater wells. Site assessments were previously conducted by the City's consultant,
Geoscience, and included evaluation of various sites as to their suitability for installation of new
groundwater wells and evaluation of the following key factors:
• Aquifer production potential
• Groundwater quality and potential environmental hazards
Well interference
• Proximity to abandoned or destroyed wells
• Access and area constraints for well drilling, equipping, and maintenance activities
• Site layout
• Potential impacts to the public
• Proximity to existing water/storm water and other utility infrastructure
• Hydraulic issues and constraints
• Site security
• Proximity to sanitary hazards
• Land use
• Preliminary cost comparisons
Based on the results of the analysis, along with supplemental hydraulic modeling, the Utilities
Yard at 9252 Stewart and Gray Road followed by the abandoned Well Site No. 27 at 7926
Springer Street in the southwest part of the City, ranked highest in terms of their benefits in
CC NO. 6866 GROUNDWATER WELLS NO. 27 AND 28 DRILLING, CONSTRUCTION,
DEVELOPMENT, AND TESTING
AUGUST 28, 2018
PAGE #2
supplying the highest level of long-term reliability and operational flexibility. Additionally, they
provide the benefit of being adjacent to two of the larger developments in the City, the
Promenade at Downey and Rancho Los Amigos, thereby providing an added level of supply
reliability for these and surrounding areas.
A Mitigated Negative Declaration was previously prepared and adopted and a vacant residential
structure at the Utilities Yard was abated and demolished in anticipation of the groundwater well
project.
Plans and specifications for the subject project are complete and the project is now ready for
solicitation of construction bids.
The scope of the groundwater well improvements includes drilling and installing conductor
casings; drilling of pilot boreholes; conducting geophysical borehole logs; conducting isolated
aquifer zone water quality testing within the boreholes; enlarging the pilot boreholes to their
ultimate diameter; installation of well casing, screen, sounding tubes, gravel feed pipes, and
associated appurtenances; installation of filter pack and annual seal; development of the wells
by airlifting and swabbing, pumping and surging; pump testing for yield and drawdown; post
installation alignment and video surveys; and completion of the wellheads.
The wells are anticipated to be drilled to depths of 1,200 to 1,500 feet with casing diameters of
20 -inches. The drilling project will be followed by another project to construct the well housing
and discharge piping, and to equip the wells with pumps and motors which are anticipated to be
300-400 horsepower depending on the results of the final yield and drawdown tests of the
drilling project. Staff recommends that the City Council approve the subject project plans and
specifications and authorize, solicitation for bids.
Efficiency & Adaptability
Quality of Life, Infrastructure & Parks
The estimated total cost of this project including the cost of design, construction, project
administration, inspection, and contingencies is $4,000,000. There are sufficient funds in FY
2018-2019 Water Fund Capital Improvement Program Account No. 51-1-8665 to cover the total
project cost.
ATTACHMENTS
Attachments A and B = Project Location Map
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CC NO. 686B GROUNDWATER WELLS NO. 27 AND 28 DRILLING, CONSTRUCTION,
DEVELOPMENT, AND TESTING
AUGUST 28, 2018
PAGE #3
CC NO. 686B GROUNDWATER WELLS NO. 27 AND 28 DRILLING, CONSTRUCTION,
DEVELOPMENT, AND TESTING
AUGUST 28, 2018
PAGE #4
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DEPARTMENT OF PUBLIC WORKS UTILITIES DIVISION
CASH CONTRACT NO. 686B
GROUNDWATER ELLS NO. 27 & 28 DRILLING,
CONSTRUCTION, DEVELOPMENT, AND TESTING
WELL NO. 28: 9252 STEWART AND GRAY ROAD Attachment "B"
Location a
ATTACHMENT B
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