Dams and Electricity: Dam It!
In the first edition of this blog, I noted that “the electric sector underpins every other essential industry sector, and it also relies on many of them. I…think of the overlaps like the Olympic rings – all interlinked, with some overlapping more than others.”
For the next several editions, I’ll continue to focus on each critical infrastructure sector in relation to the electric sector because electricity – which began to be deployed as a service close to 150 years ago – has enabled the progress, convenience and abundance that are hallmarks of modern life. Thereafter, I’ll get into the overlapping policy issues in more detail.
In this edition, I’ll discuss the dams sector and how it interacts with the electric sector. Here’s what the Department of Homeland Security’s Cybersecurity and Infrastructure Security Agency (CISA) says about the dams sector in the U.S.:
The Dams Sector delivers critical water retention and control services in the United States, including hydroelectric power generation, municipal and industrial water supplies, agricultural irrigation, sediment and flood control, river navigation for inland bulk shipping, industrial waste management, and recreation. Its key services support multiple critical infrastructure sectors and industries. Dams Sector assets irrigate at least 10 percent of U.S. cropland, help protect more than 43 percent of the U.S. population from flooding, and generate about 60 percent of electricity in the Pacific Northwest.
The Dams Sector includes more than 90,000 dams in the United States—approximately 65 percent are privately owned and approximately 80 percent are regulated by state dam safety offices.
I’ll add here that the spelling of dam is important to differentiate it from the epithet, of course. Disclaimer here in case spell-check or my fallible human eye conflate the two.
Before I take us back into the history of dams, I’ll share a personal experience. When I first began working in the electric sector as a lobbyist, I attended a meeting hosted by the Washington Public Utility Districts Association (WPUDA) where they invited congressional staff and others to engage with the engineers and technicians and to tour certain facilities. As you may know, Washington State’s Columbia River system of dams is an engineering wonder that has enabled utilities in the state to offer the lowest electric rates for decades – emissions-free and reliable. It’s been about 20 years since that first trip, so some details are fuzzy, but I believe we toured the Rocky Reach Dam owned by Chelan County Public Utility District, and the Bonneville Dam, run by the U.S. Army Corps of Engineers, with the hydropower output going to Bonneville Power Administration and its customers.
On entering the Bonneville Dam, I recall a small museum of sorts, demonstrating how hydropower worked. Having previously been to coal-fired and gas-fired power plants where complicated chemical processes are involved to remove emissions and aid in combustion, the simplicity of this process was stunningly beautiful to me. The power of falling water (the higher the downward trajectory or “head,” the more powerful the flow) spun a turbine that interacted with an electromagnet in the generator to produce electricity – that was then transmitted out to the local grid. Brilliant.
Even then, the utilities had also taken great pains to ensure that fish could traverse the dams, creating fish ladders that enabled almost all healthy fish to make it (over 99%). However, I also noticed that there were seals perched out near the fish ladders enjoying a hearty breakfast. Best laid plans. I’ve heard that, since then, accommodations have been made to level the playing field between the fish and the seals.
As we all know, beavers are the original dam makers, well before people developed the engineering chops to effectively dam water. What I didn’t know is that there are only two species of beaver – one in North America and one in Eurasia. I also didn’t know that beavers are considered “keystone species” because their dams create wetlands and other habitat for countless other species. So, humans, at least in much of the northern hemisphere, had only to notice what the beavers were doing and attempt to emulate the concept. There is no evidence in the fossil record that they were successful doing so, at least on a more significant scale, until about 5,500 years ago. This timing coincides generally with other innovations in critical infrastructure I’ve written about here, although it’s on the tail end of those major turning points.
Ancient societies had many of the same goals that CISA lays out for the dams sector today – water retention, flood control, and irrigation being primary. According to numerous sources, the Jawa Dam was the first known, functioning dam, and was a masonry gravity dam, which uses the gravity of the dam to counteract the pressure from the water. It was one of a series of dams that attempted to aid water retention in an arid area of what is now modern-day Jordan. The reinforcements used by the dam makers enabled gravity to work in favor of the dam, but that innovation was unfortunately not translated to others for many centuries. The Egyptians attempted a major dam project about 400 years after the Jawa Dam was constructed, but it failed after much investment and was abandoned. They did not come back to major dam construction for another 900 years or so, at which point they were more successful at taming the Nile at Ha-Uar dams where a reservoir was created that still exists today (in an altered form), making it close to 4,000 years old.
About 4,500 years ago, the Dholavira system of dams and reservoirs was created in modern-day India. Sometime between 2,700 and 3,700 years ago in modern-day Yemen, another major innovation in dam building occurred at the Great Dam of Marib, which was originally 13 feet high and 1900 feet in length. It was made of packed earth, triangular in cross-section and also used stonework on either side to marry it with the natural rock abutting the dam. The dam was maintained and reinforced for centuries thereafter, and the site now hosts a modern dam. The ancient Chinese constructed dams and reservoir systems as well, with the oldest verified to be from about 2,300 years ago.
As noted in the second edition of this newsletter, the Romans applied their engineering prowess and understanding of the need for water availability and mobility in their vast empire to create intricate systems of aqueducts. While not as well-known, their dam building skills rank as high as those of their aqueduct-construction, road-building and bridge-making. They began building dams in earnest around the time of Christ’s birth in 33 B.C. Several Roman innovations enabled them to build bigger dams, enabling massive reservoirs for the first time – the creation of Roman cement (a chemical combination that I should have mentioned in my last newsletter!) and hydraulic mortar ensured that water did not have a serious negative impact on the construction material, the use of arches and buttresses ensured much greater stability and enabled larger structures, and their ability to organize labor and materials for large projects (capitalizing on their transportation skills as noted in the third edition of this blog) also aided them. Of course, while slave ownership was common then, they notoriously used massive amounts of slave labor to accomplish their goals, which muted their achievements in this regard.
Dovetailing off of Roman-built bridge dams, the Persians (modern-day Iran) took the use of water to the next level – hydropower. Water wheels were inserted at the dam to turn cranks for early milling. By the 10th century A.D., this innovation was commonplace in Persia and was also used to transfer water into aqueducts for further transportation.
In Europe during the Middle Ages, the Dutch proved that necessity is the mother of invention – the low-lying land was prone to flooding without intervention. Many Dutch cities are named with “dam” included – Amsterdam being the most well-known. They created an elaborate and extensive system of dams that also served as bridges. The Dutch were the exception in Europe during this time, however, as other dam construction largely went dormant for several centuries.
While dam construction resumed in Europe beyond the Netherlands in the 1500s, major innovations did not occur again until the 1800s. With the expansion of the British Empire into North America and India, British Army engineers constructed dams there using new techniques. For example, in modern Hyderabad, India, the British engineer Henry Russel built the Mir Alam dam in 1804, and which is still in use today over 200 years later. The innovation used by Russel and in other pioneering work by the British was variable arches. A curved masonry dam was also pioneered in Canada at the Jones Fall Dam. It used sluices during construction to deflect the water and was completed in 1832.
The correlation between healthy water supplies and disease was also coming into focus around this time and a dam was constructed by Francois Zola in Aix-en-Provence in the 1850s as a direct result of a horrible cholera outbreak two decades prior. This dam is also notable because it incorporated mathematical principles into stress tests and analysis.
The work of civil engineering professor William Rankine of Glasgow University in his 1857 paper On the Stability of Loose Earth, provided the foundation (pun intended) for the innovations in dam building that have occurred since. The Rankine theory created the mathematical and scientific structure for this foundation. In the 50 years after Rankins’s theory, engineers began to perform stress tests at various points on structures and measuring interconnected results from those tests. Understanding of hydrology also improved during this time, as well as its impact on solid structures.
Even in the absence of digital technologies and computers, massive feats of engineering were undertaken in the first half of the 20th century using the knowledge derived in the previous 50 years.
The world’s largest and most complex dams have all been built within the last century, due to engineering as well as technological advances. In addition to supplying water and controlling flooding, modern dams are often constructed to provide hydroelectric power. The Hoover Dam, a concrete arch-gravity dam constructed in the Black Canyon of the Colorado River in 1936, exemplifies these 20th century advances. The dam impounds Lake Mead, is 726 feet tall and has a reservoir capacity of 28,537,000 acre feet. It also produces four billion kilowatt-hours of hydroelectric power annually, which is enough to serve eight million people. It does so through arrangements with the Western Area Power Administration and publicly and cooperatively owned utilities in Nevada, Arizona, and California. This dam was constructed two years ahead of schedule and under budget despite the grueling conditions and close to 100 worker fatalities (that is not a typo). I got to visit this marvel about eight years ago with an “owners tour” into the dam itself and can understand how dangerous it would have been during construction back then.
Other huge dams were constructed on the Columbia and other rivers subsequent to Hoover in the U.S. (although no large dam projects have been completed in 50 years), but with an increased focus in North America on safety of the workforce as well as safety in the performance of operation and maintenance. While over 900 dams in the United States have been removed since 1990, dam construction in places like China, Russia, Turkey, and Ethiopia have proceeded. China has five of the largest 10 dams in the world, including the largest, which stands at 1,001 feet. According to Tata and Howard engineering, “With the tens of thousands of existing large dams throughout the world, and the ever-increasing demand for water and power, dams will continue to make a significant impact on modern day life. And, as is evidenced by history, dam engineering will continue to evolve as additional innovations, discoveries, and technological advances are made.”
Focusing on those dams that also produce power, in the U.S. there are 1,449 out of 90,000 total dams, according to the Energy Information Administration. Some estimate that adding hydropower facilities to some of these dams could increase capacity by some 12,000 megawatts (MW), or enough to power about 12 million homes. Where hydropower exists, it significantly underwrites other uses such as water storage, irrigation, recreation, flood control, and environmental remediation (such as the fish ladders mentioned earlier). What I mean by this is that the electric customers subsidize these other functions to a greater or lesser degree, depending on the project.
In terms of ownership, the federal government owns and operates many dams, including those with hydropower. Such dams are either operated by the U.S. Army Corps of Engineers, the Bureau of Reclamation (under the Department of the Interior), or the Tennessee Valley Authority (TVA), with the output of the hydropower being marketed and, in most cases, transported by the federal power marketing administrations (PMAs) or TVA. The PMAs and TVA in turn sell the electricity generated by the hydropower to mostly not-for-profit electric utilities (public power utilities and rural electric cooperatives) although some private companies have access to purchase any excess power. Non-federal entities such as private, for-profit, investor-owned utilities and publicly owned utilities also own and operate hydropower dams (such as the Rocky Reach dam mentioned earlier) – rural cooperatives do not typically own and operate dams themselves.
Hydropower itself, whether produced from dams or otherwise (irrigation ditches, tides, run-of-the-river and pumped storage are some other forms) is a non-emitting, extremely simple and reliable resource that can also provide what is called “black-start” capability. This capability enables an electric generation to cycle back on quickly after a power outage in order to reenergize the system.
Here are some other ways the sectors overlap:
Reliance on transportation. The dams sector actually aids transportation in that it provides lock systems enabling intercoastal and inland water systems. Roads also traverse dams in many cases. The electric sector is reliant on these transportation systems.
Reliance on critical manufacturing. Dams require operation and maintenance to maintain safety with cement and other building materials needed to repair or replace facilities, including hydropower systems. The electric sector's reliance on manufactured products is extensive.
Environmental regulation. Both industries are regulated – dams for safety and environmental reasons. The electric sector works with the dams sector on these challenges and is, of course, regulated itself.
Reliance on water. When water is constrained, the plethora of dam benefits listed above are strained and can also impact hydropower production.
Workforce challenges and the knowledge drain that has resulted from retirements in recent years impact both industries’ regular operations. Both the dams sector and electric utilities must also train their workforces for future challenges such as AI deployment and other technological innovations.
Supply chain constraints that impact every aspect of infrastructure deployment and maintenance.
How to best use technology to create efficiencies and minimize expenses.
How to manage the cybersecurity risk that comes with those technology deployments. Both industries are acutely focused on this and could work even more collaboratively in the future.
I am an unabashed fan of hydropower in all forms and now better appreciate the other benefits that dams provide and the history that has informed this.