Putting Produced
Water to Work
A White Paper Prepared by CalFLOWS
T
wo industries anchor Kern County’s economy –
agriculture and oil production.
Helpful Unit Conversions
While this fact is
1 barrel =............................................... 42 gal.
well-known, it is less well-known that both industries
manage large volumes of water.
1 acre-foot =.......................................326k gal.
.................................................... 7,760 barrels
In Kern County, agriculture uses nearly 2.3 million acre-feet
of water each year (49 million barrels per day) to produce
10k bbl/day =.................................. 470 ac-ft/yr
crops worth more than $7.5 billion. This represents 15% of
10k ac-ft/yr =.................................213k bbl/day
the county’s non-government gross domestic product and
makes Kern County the nation’s second largest agriculturally
every barrel of oil produced in Kern County, approximately
productive region.1
13 barrels of “produced water” accompany it.
In Kern
While many Californians are aware of Kern County’s
County, this means 5.4 million barrels of water each day
prolific oil and gas production, it is often unknown that oil
(254,000 acre-feet per year) are brought to the surface.2
production also produces significant volumes of water. For
Finding opportunities to manage produced water is critical
1. Kern Economic Development Corporation’s 2016 Kern County Market Overview and Investor Directory and Water Association of Kern County usage statistics.
2. California State Division of Oil, Gas, & Geothermal Resources on-line database for2015.
1
Just what is produced water?
to enabling oil production. In fact, without viable alternatives
to manage produced water, oil production would decrease.
Water
that
exists
in
subsurface
hydrocarbon-bearing
Water supplied to Kern County’s agriculture industry comes
formations and is brought to the surface during oil and gas
primarily from surface water sources such as the Kern River,
production is known as produced water. Formation water
the State Water Project, and the Central Valley Project and from
exists naturally along with hydrocarbons and varies in quality
groundwater. These supplies supplement what little rainfall occurs
depending on the environment, e.g. marine, brackish, or
in the San Joaquin Valley. Various surface water supplies have
continental fresh water.
become unreliable in recent times. Severe curtailments of surface
Produced water is reused in steam generation and water flood
water deliveries from the State and Central Valley Projects (in
techniques to facilitate oil production. Approximately one-fourth of
some years farmers have received no water from these sources)
Kern County’s produced water is beneficially used within the oil
have forced farmers to rely on increased groundwater pumping
fields themselves, reducing or eliminating the need to use fresh
to meet their needs. All of these issues have forced thousands of
water for most oil and gas production activities. The remaining
acres of prime agriculture land to be fallowed.
produced water is usually reinjected back into subsurface
In 2014, California enacted the Sustainable Groundwater
reservoirs from which it came by way of specially permitted
Management Act to regulate groundwater. The Act requires that
injection wells. The injection process is regulated by the California
each groundwater basin in the state develop plans to sustainably
Division of Oil, Gas and Geothermal Resources through a
balance water inflows with pumping from the basin, much like
memorandum of understanding with the federal Environmental
individuals and businesses must balance the credits and debits
Protection Agency.
to their checking accounts. As landowners, water districts, local
How much produced water is there and generally,
what is its quality?
governments and other stakeholders come together to develop
these plans, there is a clear need for increased reliable deliveries
The graph at right illustrates the volume of produced water
from the State and Central Valley Projects and/or altogether
generated in Kern County and more importantly, how much is
new water supplies to Kern County. Without these new water
potentially available for reuse. 3
supplies, farmers will be unable to avoid fallowing hundreds of
thousands of acres of otherwise productive land. Lacking reliable
An additional 150,000 acre-feet per year (3.4 million barrels per day)
water supplies, the region’s economy will falter.
of produced water is potentially available for reuse in Kern County.
This setting – an agricultural economy dependent upon reliable
As for produced water quality, oilfields east of the Interstate 5
water supplies in the same area as oil producers managing
corridor in Kern County yield produced water that is of better
large volumes of produced water leads to an intriguing question:
quality (i.e. generally lower in hardness and total dissolved solids)
as compared to produced water on the west side. Because of
Is it possible to put more produced water to work
in Kern County?
this, fewer and less energy-intensive treatment steps are needed
to beneficially reuse eastside produced waters.
This paper explores that very question.
3. Total produced water by year represents DOGGR records for Kern County.
2
300,000
6,000,000
250,000
200,000
4,000,000
150,000
3,000,000
ACRE FT/YR
WATER (BPD)
5,000,000
100,000
2,000,000
50,000
1,000,000
0
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
YEARS
USED IN OIL PRODUCTION
CURRENTLY TO AG IRRIG
How much produced water is being put to
beneficial use?
FOR POTENTIAL ADDITIONAL BENEFICIAL USE
Outside of Kern County, there are examples of produced water
being put to beneficial use where produced water treatment plants
supply treated water to benefit nearby surface/groundwaters:
A signiciant portion of produced water is used beneficially as
part of oil and gas production itself, e.g., for steam generation
 The first example is near the City of Pismo Beach in San
and other enhanced oil recovery techniques. In addition to that,
Luis Obispo County. In operation since 2013, this treatment
several eastside oil fields have supplemented supply to 34,000
plant is permitted to discharge 20,000 barrels per day (940
acres of crops for more than 20 years. An average of 600,000
acre-feet per year) to Pismo Creek.
barrels per day (28,300 acre-feet per year) of treated produced
 Another example is in Monterey County along the Salinas
water has been beneficially used within areas of Cawelo Water
River. This treatment plant is permitted to introduce 50,000
District, located just north of the City of Bakersfield.4
barrels per day (2,350 acre-feet per year) for aquifer
For the North Kern Water Storage District located to the west of
recharge. It has been in operation since 2007.
the Cawelo Water District, treated produced water is being used
for irrigation and groundwater recharge with permits in place to
In each case, various steps take produced water and treat it to
deliver 21,200 acre-feet per year (451,000 barrels per day).
meet permit limits for use outside of the oil field, whether it be
irrigation, stream flow augmentation, environmental restoration,
4. Chevron / Cawelo Water District / Valley Water Management Co. joint presentation to the Central Valley Regional Water Quality Control Board’s Food Safety Panel, January 2016
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or groundwater recharge.
Water processing and treatment
more produced water to work means a more stable economy
depends on the quality of the water as it is produced and its
for everyone in Kern County, and an increase in local water
intended beneficial use.
supplies and local supply reliability.
Could even more produced water be put to
beneficial use?
The California Forum for Leadership on Water Solutions
(CalFLOWS) was organized to be a unified voice in support
of finding new, sustainable water supplies to meet California’s
The simple answer is “yes.” More produced water could be
growing water needs and ensuring that beneficial reuse
treated and put to use in Kern County. The challenge is finding
of treated produced water is part of the solution. Consider
commercially and economically viable projects for beneficial
participating in CalFLOWS to learn more, stay connected, and
reuse to transform treated produced water into new water
play a part in innovating California’s water future.
supplies for irrigation, banking, groundwater recharge or other
uses. Public-private partnerships that bring together varying
industries and government entities represent a promising
pathway to successful reuse of even more produced water.
Related to this, Kern County’s recently adopted Oil & Gas
Zoning Ordinance requires additional produced water reuse.
Oil producers are to “work with local agricultural producers and
water districts to identify new opportunities to increase the use
of produced water for agricultural irrigation”. The stated goal is
30,000 acre-feet per year (640,000 barrels per day) in addition to
existing produced water uses. Further, in June 2016, California’s
State Water Resources Board released a new general order to
help promote water recycling projects, including the development
of new “water reclamation requirements.” This new general order
CalFLOWS – California Forum for
Leadership on Water Solutions
is an attempt to provide regulatory clarity throughout California
that incentivizes investment in water recycling facilities.
Where do we go from here?
www.calflows.com
Putting more treated produced water to work in Kern County
will sustain energy production while helping the county find
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solutions for its growing water needs. For oil and gas producers,
it means improved reservoir management and increased
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partnership with local communities. For water managers and
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irrigators, it represents potentially new water supplies outside
of existing surface and groundwater resources. Overall, putting
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