and privately stored on the blockchain.
The team is piloting its approach in the Solano Subbasin, a
proposed high-priority subbasin with more than 30,000 acres of
groundwater-dependent irrigated lands. The Solano Subbasin
is an aquifer within the Sacramento-San Joaquin Basin, which
drains into the Delta. The Delta is often referred to as the nexus of
California’s statewide water system. It covers 1,100 square miles
and provides water to Silicon Valley and coastal and southern
California and supports dozens of legally protected fish, plant
and animal species. In addition, nearly 75 percent of this land is
used for agriculture.
With agriculture’s heavy reliance on groundwater for irrigation,
and the need for sustainable management of this dwindling
resource, the mantra “you can’t manage what you don’t measure”
has gained a significant meaning. By using a system designed to
maintain sustainability for groundwater-dependent ecosystems and
communities, water users may one day be able to trade groundwater
shares through their mobile devices.
Moving Toward Sustainability:
Groundwater Banking and Trading Scenarios
The pathways toward achieving sustainability in a subbasin
can vary. One approach gaining traction is a market-based system
for groundwater share trading. A groundwater trading system
treats groundwater as an exchangeable, valued asset within a
resource-limited system, in a manner analogous to the systems used
to trade carbon offsets. Users could purchase, lease, sell or bank
shares. The trading framework and rules can be defined through
a GSP to both protect groundwater-dependent ecosystems and
vulnerable communities that rely on domestic wells for drinking
water, while also providing flexibility for agricultural users to buy
and sell groundwater shares.
Groundwater trading systems have the potential to incentivize
environmental improvements and water use efficiencies while
easing the burden of achieving SGMA’s sustainability mandates.
A successful groundwater trading system requires clear protocols,
quality standards, data collection
methods and transaction accounting.
Potential limitations include:
• The high cost of purchasing,
installing and maintaining
groundwater well meters and the
accuracy of metered data over time.
• The concern from groundwater users
about privacy of the groundwater
use data collected by the meters.
• The lack of trust in a centralized, non-local
“banking” or trading system
and the potential for cyberattacks on
With these concerns in mind, the
team is piloting technologies that can
accurately monitor groundwater use
through a forgery-proof and transparent
platform that allows local users to track
and exchange groundwater shares. Two
key technological features of this pilot
program address the potential limiting
factors to building a system of this kind: IoT sensors and blockchain-enabled
IoT connects sensors and other devices over communications
networks to global databases. The IoT market is anticipated to reach
around 25 billion connected devices by 2020. Large sets of data can
be processed and made accessible to speed up decision-making. In
the water sector, these tools can help integrate existing public water
data and connect water users and local agencies to address near-term
water management problems.
For example, in Africa, SweetSense teamed up with nonprofits
and government agencies to use IoT sensor technology to create a
proactive system that alerts local technicians when rural drinking
water wells need servicing. The project, supported by USAID, is
currently monitoring the water supply for two million people across
Ethiopia and Kenya and will expand to five million this year in an
effort to end drought emergencies.
In a unique technology transfer from Africa to North
America, a similar approach is being used for the groundwater
monitoring pilot program in the Solano Subbasin. The noninvasive
sensors from SweetSense are compatible with electrically driven
groundwater pumps, linking run-time data over satellite networks
without requiring specialized electrical or plumbing work. IoT
sensors require minimal power to operate, minimal training
to install, do not rely on Wi-Fi or cell service and can operate
without maintenance for extended periods of time. These features
should work well in California’s remote and power-constrained
The sensors detect the electrical current flowing through the
power line to the groundwater pump. These power-draw data are
then transmitted to a sensor gateway, which uploads the data daily to
a Swarm Technologies satellite network. Water level loggers will also
be integrated into some production wells to estimate overall water
extractions. This remote monitoring approach will be tested for two
years to validate its accuracy for measuring groundwater extraction.
Water management system used in Africa by IBM Research and SweetSense to integrate groundwater well
sensors to a cloud-based monitoring platform.