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The Hoover Dam's deadpool level is 895 ft, or 272 m. I am not a civil engineer, but why not build the water intakes (apologies if I don't use the correct termin

The Hoover Dam's deadpool level is 895 ft, or 272 m. I am not a civil engineer, but why not build the water intakes (apologies if I don't use the correct terminology) at the bottom of the dam, in order to set the deadpool level at 0 ft? Why build the intakes so high?

katbyte 4y ago
You wouldn’t have as much hydraulic head pressure. The lower the intakes the shorter the pen stocks the less power you produce.
atwood22 4y ago
Because the water needs potential energy to do work.
- i_love_hackers 4y ago
  just like hackers! :-) :D :O
ml_giant 4y ago
I did some googling since I was also curious and found this stellar article: https://energyeducation.ca/encyclopedia/Hydraulic_head https://energyeducation.ca/encyclopedia/Hydraulic_head TL:DR: "Head differences of 100 meters or higher are considered high head. In this type of plant, water travelling through the turbine comes from a significantly higher elevation, meaning that the system needs a smaller volume of water to produce an equivalent amount of energy.[1] These systems generally also require smaller turbines since there is less water flowing through the turbine."
- digdugdirk 4y ago
  Props for finding a simple yet thorough article explaining many of the terminology used in other responses in this thread. Thank you.
- cratermoon 4y ago
  The ideal place for a hydroelectric dam is what's called a slot or "gunsight" canyon. Narrow and high, to create the best conditions with the smallest dam. Dams in wide, relatively flat places like along the Columbia River exist, but they are multi-purpose, built for flood control, irrigation, navigation (with channels and locks), and recreation benefits in addition to hydroelectric.
giantg2 4y ago
At 0 feet, you will end up with silt being sucked though or accumulating/clogging. Also, the intakes are likely below the stated level, but you need X number of feet above that for water pressure to turn the turbines. Either way, I'm not sure that a retrofit is a feasible option.
- Victerius 4y ago
  > you will end up with silt being sucked though or accumulating/clogging A big filter at the intake?
  - giantg2 4y ago
    That still doesn't solve the pressure part of the problem, and likely makes it even worse.
  - deleted 4y ago
    [deleted]
  - shadowgovt 4y ago
    Filters have to be cleaned, a process that is both expensive and dangerous at the bottom of a reservoir that high. Which is why the better solution is to put the intakes up a bit and allow the bottom of the reservoir to serve as a settlement pool.
baggy_trough 4y ago
895ft is measured from sea level.
Vvector 4y ago
The measurements given are from sea level. The deadpool height of 895ft (above sea level) is the output level, where the water dumps downstream. The intakes have to be above this height.

katbyte 4y ago

You wouldn’t have as much hydraulic head pressure. The lower the intakes the shorter the pen stocks the less power you produce.

atwood22 4y ago

Because the water needs potential energy to do work.

i_love_hackers 4y ago
just like hackers! :-) :D :O

ml_giant 4y ago

I did some googling since I was also curious and found this stellar article: https://energyeducation.ca/encyclopedia/Hydraulic_head https://energyeducation.ca/encyclopedia/Hydraulic_head TL:DR: "Head differences of 100 meters or higher are considered high head. In this type of plant, water travelling through the turbine comes from a significantly higher elevation, meaning that the system needs a smaller volume of water to produce an equivalent amount of energy.[1] These systems generally also require smaller turbines since there is less water flowing through the turbine."

digdugdirk 4y ago
Props for finding a simple yet thorough article explaining many of the terminology used in other responses in this thread. Thank you.
cratermoon 4y ago
The ideal place for a hydroelectric dam is what's called a slot or "gunsight" canyon. Narrow and high, to create the best conditions with the smallest dam. Dams in wide, relatively flat places like along the Columbia River exist, but they are multi-purpose, built for flood control, irrigation, navigation (with channels and locks), and recreation benefits in addition to hydroelectric.

giantg2 4y ago

At 0 feet, you will end up with silt being sucked though or accumulating/clogging. Also, the intakes are likely below the stated level, but you need X number of feet above that for water pressure to turn the turbines. Either way, I'm not sure that a retrofit is a feasible option.

Victerius 4y ago
> you will end up with silt being sucked though or accumulating/clogging A big filter at the intake?
- giantg2 4y ago
  That still doesn't solve the pressure part of the problem, and likely makes it even worse.
- deleted 4y ago
  [deleted]
- shadowgovt 4y ago
  Filters have to be cleaned, a process that is both expensive and dangerous at the bottom of a reservoir that high. Which is why the better solution is to put the intakes up a bit and allow the bottom of the reservoir to serve as a settlement pool.

baggy_trough 4y ago

895ft is measured from sea level.

Vvector 4y ago

The measurements given are from sea level. The deadpool height of 895ft (above sea level) is the output level, where the water dumps downstream. The intakes have to be above this height.