Located on the Colorado River, the Hoover Dam is one of America's most significant engineering feats. There are so many reasons to visit the Hoover Dam, including marveling at the reservoir it forms and how useful the water supply is. Just how deep is the water in front of the dam, though?
Short answer: On average, the depth of the water in front of the Hoover Dam is around 350 feet (107 meters).
Long answer: The depth of the water in front of the Hoover Dam varies depending on the water level in Lake Mead, which is the reservoir formed by the dam. The depth may be significantly less during low water levels.
What Was the Deepest Point in Lake Mead Ever?
The deepest point in Lake Mead ever recorded was about 590 ft (180 m) below the water's surface. This depth was reached in the early 1980s when the lake was at its maximum capacity.
Since then, due to drought and increased water usage, the water level in Lake Mead has dropped significantly. Sadly, we have been watching the water level drop lower and lower on our daily tours to the Hoover Dam.
What Is the Current Depth of Lake Mead?
The current depth of Lake Mead can vary depending on the water level. Several factors, such as precipitation and water usage, come into play.
However, as of May 2022, Lake Mead has reached its lowest water level since it was first filled in the 1930s due to a prolonged drought and over-allocation of water from the Colorado River. The deepest point is now around 400 ft (122 m) below the surface.
As of 2021, the overall water level dropped to an elevation of 1,071.56 ft (326.73 m) above sea level, which is about 140 ft (43 m) lower than the historical average. The lake's volume is around 44% of its capacity.
You can see just how drastic and quick the change has been by taking a look at two side-by-side satellite photos that NASA took of the lake, one in 2000 and the other in 2022.
How Much Water Does Lake Mead Hold?
Lake Mead's maximum capacity is roughly 31 million acre-feet (38.2 km3). This was measured in 1935, as construction of the Hoover Dam was drawing to a close. However, since then, sediments and changes in the Colorado River's flow have likely caused the capacity to decrease a bit.
This capacity was measured at the maximum elevation of Lake Mead that the Hoover Dam can handle: 1220 ft (371 m) above sea level.
The lowest elevation that the lake can be at while still being able to generate power is 950 ft (290 m). At elevations between 950 and 895 ft (290 and 273 m), the lake can't generate power but it can still release water downstream to the base of the dam. If it drops below that, it won't be able to release water downstream.
The actual amount of water Lake Mead holds has fluctuated quite a bit over the decades, though it is now at an all-time low. As of August 2023, the water level at Lake Mead is roughly 1,063 ft (319 m) above sea level.
Can Hoover Dam Run Out of Water?
As mentioned, it's possible for the water level in Lake Mead to drop to the point where the dam cannot generate hydroelectric power. However, it's very unlikely that the lake would completely run out of water.
The Bureau of Reclamation, which manages the dam and the lake, has several management plans to ensure that water is allocated relatively and sustainably among the various users in the Colorado River basin. The Hoover Dam was designed to operate with a lower water level and can still produce hydroelectric power even if the water level drops significantly.
The Hoover Dam's power generation capacity is based on the height difference between Lake Mead's water level and the outlet that works at the dam's base, called the "head." As long as there's an elevation difference, the dam can generate hydroelectric power. The low water level of Lake Mead decreases the head and thus reduces the dam's power generation capability.
It's important to note that the Hoover Dam is one of several components of the more extensive Colorado River system. It includes other dams and reservoirs upstream. In extreme drought, water can be pumped from other reservoirs to keep Lake Mead's level from dropping too low.
What Will Happen If Lake Mead Dries Up?
If Lake Mead were to dry up, it would significantly impact the region in three main ways:
The Hoover Dam relies on a steady water supply from Lake Mead. Without enough water, the dam would not be able to generate power. This would have ripple effects on the power grid and the economy, as the dam provides power to several states in the southwest United States.
Aside from generating power, Lake Mead is a significant water source for Arizona, Nevada, and California. The water shortage in the lake would also affect the people and industries that rely on the lake for agriculture, municipal water supply, drinking water, and recreation.
Last but not least, Lake Mead is an essential habitat for fish and other wildlife (both aquatic and non-aquatic). The loss of the lake would seriously hurt these species.
Related Reading: What Happens If Hoover Dam Shuts Down?
It's worth noting that the likelihood of Lake Mead completely drying up is extremely low due to the Bureau of Reclamation's management plans and the fact that the water level in the lake is closely monitored and managed. However, there is a chance that the water level could drop below the capacity for generating power and releasing water downstream.
Even if the water level drops significantly, contingency plans are in place to ensure that the lake's water supply is used as reasonably and sustainably as possible, across the many locations that depend on it.
The depth of the water in front of the Hoover Dam has varied over years, largely impacted by the depth of Lake Mead, which has been on a fairly steady decline recently. In the 1980s, Lake Mead reached its peak depth of 590 ft (180 m) below the surface. Now, the lowest depth is about 400 ft (122 m).
It's worrying to see the lake's water level decline but the chances of it fully drying up are very slim. The Hoover Dam and Lake Mead still do so much important work for the southwest USA, in terms of both water supply and power generation.