HomeMy WebLinkAbout11 Asterra Leak Detection ContractTRUCKEE DONNER
Public Utility District
MEETING DATE: August 3, 2022
TO: Board of Directors
FROM: Neil Kaufman, Water System Engineer
Chad Reed, Water Utility Director
AGENDA ITEM # 11
SUBJECT: Consideration of Contract with Asterra to Perform Leak Detection
Services
APPROVED BY:
Brian C. Wright, General Manager
RECOMMENDATION:
Authorize the General Manager to execute a contract with Asterra to perform leak
detection services in an amount of $39,150, plus a ten percent change order allowance
of $3,915, for a total authorization not to exceed $43,065.
BACKGROUND:
All water distribution systems experience some level of Non -Revenue Water (NRW).
NRW is water that is introduced into the distribution system at the wellhead, but the
District does not receive any revenue for this water from an end user. NRW typically falls
into three categories:
• Unbilled authorized consumption: This is intended water usage that is not
metered and not billed. This typically involves activities such as firefighting, water
system construction and maintenance, and system flushing;
• Apparent Losses: This includes water not measured to due metering errors,
water used by unauthorized connections and water theft.
• Real Losses: This is water lost to due to leaks on piping, storage tanks and other
distribution system facilities.
Page 1 of 4
The State of California is in the process of developing regulations regarding NRW. It is
expected that the District will be subject to requirements in all three areas of NRW. For
the District, it is currently estimated that about 30% of the water pumped into the
distribution system is lost to NRW, with real losses (system leakage) as the great majority
of NRW.
In an effort to address water loss within the District, staff has implemented several
different approaches. Some of these methods are acoustic leak correlation which helps
to locate leaks and identify leaks that have not surfaced. Staff was able to identify and
repair 64 leaks within the water system last year. To further the District's efforts in water
loss reduction, an operational position within the water utility staff has been added. The
meter maintenance and water loss coordinator will oversee the meter testing and
replacement, leak detections, and water loss reduction programs. Historically, the District
has completed one water main replacement project a year. With the increase in the
Capital Improvement Plan, additional and/or expanded main projects are in the future.
This is a measurable element for the District's water loss program.
Most years, the District undertakes a pipeline replacement project. These projects target
water mains known to be in poor condition and have helped to reduce water system real
losses. In addition, District field crews strive to repair leaks on a timely basis in order to
minimize the water lost due to leaks. Identifying and locating leaks in a timely and efficient
manner is critical to any leak repair program.
As the District implements projects that reduce the water loss throughout the District, new
methods and practices are being examined such as identified in the Strategic Plan as the
"New Leak Detection System Technologies". A staff priority is addressing leak repairs and
leak detection in a timely manner. The reduction on demand from the District's wells will
reduce power demands annual experienced by the District. These project not only support
the vitality of our water resources; they also support the District's commitment in
stewardship of the Martis Valley Water Basin and reduction of greenhouse gasses (GHG)
associated with pumping water.
In the past, a number of leak detection surveys have been performed by District field
crews and outside contractors. These surveys have been performed using acoustic leak
detection equipment and have had limited success at locating leaks. The most recent
survey was performed by an outside contractor in 2020. It covered about 27 miles of pipe
at a cost of about $16,000. This key informational element focusses staff on assessing
areas of concern.
ANALYSIS:
The core technology Asterra uses to locate leaks was first applied in the search for
underground water on Mars and other planets. The geophysicist that developed this
technology have discovered it can also be used to detect leaks within municipal water
systems. These geophysicist then created the company Utilis the parent company of
Asterra in 2013 and further developed leak detection technology and make it available
commercially in 2016.
Page 2 of 4
Asterra utilizes satellite based imaging and synthetic aperture radar to detect water leaks
on water distribution system piping. This technology has the capability to detect water
leaks that are not visible at the ground surface to a depth of about ten feet. It is hoped
that this new leak detection technology will allow to District to locate the leaks that are not
surfacing.
Asterra conducted a similar leak detection project for the South Tahoe Public Utility
District (STPUD) in the summer of 2021. During this project, Asterra analyzed about 320
miles of pipeline and identified 114 locations that warranted further investigation. The field
investigations confirmed leaks at 22 of the locations. Actual repair of the leaks was not
included Asterra's scope of work. STPUD staff stated that they were very satisfied with
the results of the project and indicated that STPUD was considering a contract with
Asterra to perform a similar leak detection project on an annual basis.
Asterra has provided a price proposal of $39,150 to the District. This covers leak
detection analysis of the District's entire water distribution system, which is about 235
miles of pipe. The planned scope of work for the District involves two items:
• Conducting the satellite analysis to identify suspected water leaks; and
• Conducting ten days of field investigations using acoustic detection methods to
verify the leaks identified by the satellite analysis.
OBJECTIVES & GOALS:
This item is in support of the following goals and objectives:
District Code1.05.020 Objectives:
3. Provide reliable and high quality water supply and distribution system to meet current
and future needs.
Strategic Goals:
1. Manage for Financial Stability and Resiliency
FISCAL IMPACT:
The price proposal from Asterra is $39,150. A ten percent change order allowance of
$3,915, for a total authorization not to exceed $43,065.
The FY 2022 budget includes $35,000 for leak detection services (GL account
2.7.634.20.500). Approval of this contract creates an over -budget expenditure range of
$4,150 at contract price to $8,065 if all of contingency utilized. There is sufficient funds in
the Water Operating Reserve ($5.237 million balance 12/31/2021) to cover the additional
cost over budget.
ATTACHMENTS:
None
Page 3 of 4
Page 4 of 4