I've been to Hoover Dam four times, but not for about 10 years. After 9/11, the government realized the vulnerability of the dam to a terrorist attack since a major US highway traveled over it, including trucks, RVs, and cars, so planning began for a bridge downstream to take traffic off the dam (ala Glen Canyon Dam and bridge.) The old highway had also slowed through-traffic by 30 minutes or more and created huge congestion problems over the dam.
Here's a photo of the finished project. A major reroute of highway 93 (Great Basin Highway) was also required.
Planners included a pedestrian walkway on the dam side of the bridge, accessed by a switchbacking ramp or optional stairs to get visitors from the parking lot (located on the old road which takes visitors to the dam, now called Hwy. 172 or Hoover Dam Access Road) to the bridge level. The bridge has been named to honor a former governor (Mike O'Callaghan) and former football star turned Army Ranger, Pat Tillman.) Several dozen interesting displays explain the design and construction of the bridge and give info on the two honored men, both of whom died in 2004. The bridge and bypass highway were opened in 2010.
The pedestrian walkway affords visitors with an ideal viewing platform from which to observe the dam as seen below. Click to enlarge photo and you'll see the new five story parking garage on the far left of photo. They had to blast out more mountain to build it and re-route thad to re-route the old highway a bit, now seen as a bridge between the garage and cliff edge. A gift shop and restaurant are also available now.
Last time I was here I had an even better view. I was on an Elderhostel four day kayaking program and we used a dam service road to reach the river and our put-in right at the bottom of the dam, from where we paddled 40 miles through Black Canyon, camping three night and taking hikes up side canyons. Here are photos of that trip.
Here's a view of Lake Mead and the marina...
There have been a number of changes since my last trip here. First, the five story parking garage has been constructed which helps alleviate parking concerns. Of course, they charge you to use it ($7.) Then you have a serious security check to get into the new and improved Visitor Center, much like at an airport. Unfortunately, they also charge for entrance to the Visitor Center, another $8 -- guess they have to pay it off, too. Then, the once free and later quite inexpensive dam tours are now $35.