In the case of Three Gorges Dam, over
360 million people live
within the watershed. If unprecedented
amounts of rain inundate the dam’s
spillway, the results for the country
could be disastrous.
percent of average
annual levels. And a
key reservoir in Bra-
zil dropped below 10
percent of its capac-
ity in January 2015,
Too much water poses new risks, as well. “Depending on the region, climate
change can, and probably will, affect the severity, duration and time of year of
extreme [rainfall] events,” says Mr. Mercier.
From a strategic perspective, that means sponsor organizations may want to
assess the benefits of upgrading facilities or installing new turbines to capture
additional capacity. For example, Mr. Mercier manages the Mactaquac Hydroelectric Generating Station project, based in New Brunswick, Canada. Portions
of the station will reach the end of their life span in 2030, so Mactaquac has
identified three options for the future of the station. Because each potential project plan has its own implications for the community and the
environment, the company is including a broad range of stakeholders,
from expert climatologists to First Nations communities, in the decision-making process.
Climate change is increasing risk on the technical side of things.
Maximum precipitation values determine the size and operating
parameters of a dam’s spillway, for example. So better forecasting tools
are needed to make the right engineering decisions, says Mr. Mercier.
“It’s important because it affects the risk profile of the investment as
Hydropower megaprojects like the Three Gorges Dam in China prove
just how serious that risk can be. Historically, dams were built in remote
locations away from large population centers. But in the case of Three
Gorges Dam, over 360 million people live within the watershed. If unprec-
edented amounts of rain inundate the dam’s spillway, the results for the country
could be disastrous.
“Against the backdrop of the global warming, the risks faced by our large
engineering projects have increased,” Zheng Guoguang, head of China’s Meteorological Administration, told state newspaper Study Times, according to
Reuters. “Global warming affects the safety and stability of these big projects,
as well as their operations and economic effectiveness, technological standards
The Water Cycle
Despite these warnings, some hydropower sponsors are reluctant to include
climate change models in their project plans. With
climate change hydrology still in its infancy, tools
are currently being developed to adequately cap-
ture the effects of global warming on hydropower
projects. “It’s easier for designers and sponsors
of much larger projects to include refinement of
climate change effects forecasting tools in their
design, which is why you usually see public owners
with more resources taking the lead on this,” says
Mr. Mercier.
With the support of large utility companies, orga-
nizations like Ouranos, based in Montreal, Quebec,
Canada, are trying to improve the quality of the
available data. Ouranos conducts climate monitor-
ing projects and hydropower adaptation studies
for Canada’s energy sector.
One of its current research
projects studies recent his-
torical rainfall patterns for
use in simulation models
for several watersheds in
Canada where large dams
are located. The project aims
to determine maximum
precipitation amounts and
flood levels under chang-
ing climate conditions,
which will make it easier for
hydropower project plan-
ners to take climate change into account during the
decision-making processes.
Still, normal annual variability may mask long-term trends. “We may not see the effects of climate
change for 20-30 years,” says Mr. Mercier. Since
large hydropower projects typically expect to
recoup the bulk of their costs within the first 15
years of operation, some sponsors are reluctant to
invest money into projects without a clear ROI,
Mr. Mercier says. “Owners who decide to trust the
science may not know if their investment paid off
for many years.” —Tegan Jones
“Against the
backdrop of the
global warming,
the risks faced
by our large
engineering
projects have
increased.”
—Zheng Guoguang, China’s
Meteorological Administration,
to Study Times
Three Gorges Dam, China
