# Dam it.

**URL:** <https://boards.straightdope.com/t/dam-it/207282>\
**Category:** Factual Questions\
**Created:** [October 13, 2003, 11:34pm UTC](https://boards.straightdope.com/t/dam-it/207282 "2003-10-13T23:34:37Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![ltfire](https://avatars.discourse-cdn.com/v4/letter/l/7ea924/32.png) [@ltfire](https://boards.straightdope.com/u/ltfire)\
**Post date:** [October 13, 2003, 11:34pm UTC](https://boards.straightdope.com/t/dam-it/207282/1 "2003-10-13T23:34:37Z")

</div>

What did they do with the water while they built the Hoover Dam? For that matter, same question for any dam. Diversion?

---

<div class="post-metadata">

**Author:** ![enipla](https://avatars.discourse-cdn.com/v4/letter/e/54ee81/32.png) [@enipla](https://boards.straightdope.com/u/enipla)\
**Post date:** [October 13, 2003, 11:37pm UTC](https://boards.straightdope.com/t/dam-it/207282/2 "2003-10-13T23:37:11Z")

</div>

From the specials I’ve seen on the Hoover/Glen Canyon dam. They diverted it through HUGE tunnels to either side of the dam.

Amazing stuff.

---

<div class="post-metadata">

**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\
**Post date:** [October 14, 2003, 12:04am UTC](https://boards.straightdope.com/t/dam-it/207282/3 "2003-10-14T00:04:14Z")

</div>

From the [Hoover Dam Faqs](http://www.usbr.gov/lc/hooverdam/History/tunlfaqs.html):

> [@](#):
>
> The river was diverted around the dam site through four 50-foot diameter tunnels, two on each side of the river drilled through the canyon walls. The tunnel, with a total length of 15,946 feet, or about 3 miles, were excavated to 56 feet and lined with 3 feet (300,000 cubic yards) of concrete. The tunnels could carry over 200,000 cubic feet - more than 1.5 million gallons - of water per second!