Wahweap Main Ramp Extension

[JFRCalifornia]

Sounds like there was some kind of temporary gravel down to 3,519 in 1963. I guess we will find out more in the months ahead.

Or it may have meant that if the lake was below 3519, other physical restrictions in Wahweap Creek would make launching problematic. The paper noted that the Kane Creek Road completely disappeared when the depth at the dam was at 370 feet, or at 3502. It said you would not be able to launch at Wahweap until the lake rose 17 feet from there.... What that statement means is a matter of interpretation...

Here's the actual passage from the paper:

“The Kane Creek Road dips and crosses several major lateral canyons as it leads to its destination. Lake Powell will ultimately inundate many sections of this roadway and rising canyon water will first reach it at Padre (Navajo) Canyon several miles from Kane Creek. When this is about to occur the National Park Service will close this road to all traffic. Boat launching activities will then shift to Wahweap itself, the permanent base for all future recreation activities in lower Glen Canyon. Since an additional rise of approximately 17 feet will be needed to bring Lake Powell up into Wahweap Creek far enough to permit launching, activities may need to be suspended temporarily.”

That last line implied that there was a 17-foot window (between 3502 and 3519) where the lake was too high to allow launching on Kane Creek Road, but too low to launch at Wahweap.

 

[drewsxmi]

I'll put in a photo request for anybody in the area, could you get a picture matching Rivergoer's looking across the ramp exactly at the end of the concrete when the water level is exactly at the concrete (or within a couple of inches below it vertically)? I'll use that as a reference for the exact level of the end of the concrete ramp (until it gets extended) for future reference. Get the exact date that the photo was taken.

 

[Eagle Rock]

<snip>

For those interested, I'm attaching the whole document ... Here's a link, and a couple of key takeaways...

http://www.nativefishlab.net/library/textpdf/10112.pdf

1. The short-term plan to launch boats in the very early days of the lake was to do it from Padre Canyon via Kane Creek Road, until the road itself began to submerge under the lake, at which point you'd launch from the end of the road as it dipped underwater. (!) The road to Kane Creek originated at Wahweap and was 25 miles long.

2. After the road to Kane Creek went under, launching would shift to Wahweap Creek (pre-marina), but launching there would only be possible once the lake rose to 387 feet at the dam (lake elevation 3519). (Presumably access to Wahweap Creek and/or depth at key spots would become issues.)

3. The original launch ramp at Wahweap was to be 1100 feet long (with a 500-foot gravel extension), and was to be 200 feet wide, at an 8.5% grade. The lowest edge of the permanent launch ramp at Wahweap would not be usable until the lake was 420 feet deep at the dam, or at elevation 3552.

4. A direct quote from the paper: "The NPS has made plans to accommodate launching regardless of the elevation of the lake surface."

I looked at the Lake Powell Water Database to see how accurate those predictions were. The original paper said launching at Wahweap (at 3519') should be possible by summer 1963, only a few days or a week after flooding (at 3502') closed access to the Kane Creek road. Instead, 3502' wasn't first reached until June 23, 1965. It then took another 16 days until 3519' was first reached on July 9, 1965. It would be interesting to look for boating reports for that late June-July period in 1965 - maybe in the Page newspaper?

 

[JFRCalifornia]

I looked at the Lake Powell Water Database to see how accurate those predictions were. The original paper said launching at Wahweap (at 3519') should be possible by summer 1963, only a few days or a week after flooding (at 3502') closed access to the Kane Creek road. Instead, 3502' wasn't first reached until June 23, 1965. It then took another 16 days until 3519' was first reached on July 9, 1965. It would be interesting to look for boating reports for that late June-July period in 1965 - maybe in the Page newspaper?

Very interesting observation.

Also interesting is that USBR managed to keep the lake at a rock steady 3490 from August 1964 to June 1965, probably to maintain minimum power pool (and maximize power output when the runoff started really cranking in spring 1965), but they might have also recognized that if it rose above 3502, then the Kane Creek Road launch was doomed. You'll notice that the lake started rising fast around June 15, 1965, hitting 3533 in early August. You can see the USBR allowed massive outflow of around 50,000 cfs (!) until June 25, when they shut it down to 10K and the lake really started rising fast. I know the heavy winter of 1964-65 led to a big runoff spring/summer, but I also have to think USBR took advantage of that to accommodate the transition from Kane Creek to Wahweap. You can see in the database that the window from 3502 to 3519 lasted only from June 22 to July 9 that year, but that's the window where launches would have been problematic--too high for Kane Creek Road, but too low for Wahweap...

I'm attaching the Water Database graph from 1964-66 so you can see the pattern...



The lake stayed well over 3525 through the rest of 1965 into the summer of 1966. But it fell again later that year dropping below 3519 by New Years Day 1967 and just kept on sliding to 3502, not recovering above 3519 until June 1967. So the lake was in that launch "dead zone" of 3502 to 3519 zone from January to mid-June 1967... not much lake activity then, but I wonder what they did for launching in spring 1967?

I'd check old accounts of March-June 1967 if they exist...

Here's the lake level pattern from 1966-68... pay attention to the first half of 1967...