QC
Supreme Mariner
- Joined
- Mar 22, 2005
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I saw a post in the Channel Marker thread from rjlipscomb about concern for underwater obstacles at Lake Mead. Some of you may have seen various posts of mine on this topic. In general I think people are way too worried at Mead due to significantly lower water levels in the last 5 or 6 years. With that said . . . during my 35+ years of boating on the Colorado River and her various Lakes I have hit everything you can imagine, but of course I have learned something each and every time. Most of my issues have been on the actual River itself, between the Lakes, where water levels rise and fall every hour. On Lake Mead, however, water levels rarely change more than 6 inches a day, and recently have been running only about one or two inches up and down from day to day. The point being that a typical weekender at Lake Mead should not have to consider a change of level during any specific trip at all. The exception would be anyone beaching a cruiser or houseboat for an extended time. In those cases it is possible to get seriously stuck over the course of a few days. With this exception understood, along with the variable conditions at the six paved launch ramps, I honestly believe it doesn?t matter what the water level is at all. Same issues, same safety method, annnnnd . . . lower water levels means more beaches 
So here is my daily-lake-depth-confirmation-method that has kept me from hitting anything at Mead for over 20 years. This method works probably anywhere, even offshore, but I hear the concern more with Mead simply because we are down 115 ft.
Looking around any part of Mead you can see the whitish stripe indicating the part of the shore that was previously underwater:
It also shows the basic color of everything underwater there . . . white. If you have a depth sounder you can confirm my method, but you can also do this by jumping in and swimming . . . While traveling along you will see the same basic color of water: a dark, greenish blue. Find any lighter shade of green and carefully float over it. Check the depth sounder. Now try the same with even lighter color shades. I do this the first day of every trip. This gives me a reconfirmation of what my eyes tell me about depth and is specific to that area?s water clarity and the sky that day. What I have found is that I can easily see "color" (lighter shade of green than the surrounding water) at 20 feet, and often 30. I can also tell the difference between 20, 10 and 5 feet if I pay attention.
There are very few spots on the entire Lake that contradict this method. Basically any weed clumps that might darken the underwater obstacle, but these are most common right near the shore and are not a legitimate concern in open water. Also, wherever the Colorado is currently dumping her beautiful, namesake mud, you can chuck any method out the window because the difference between 20 feet and 2 inches is not discernible at all This happens to be right at Sandy Point now, but most never even see this area as it is roughly 50 miles from Echo and Callville.
Also, another tip I have learned about all of the Colorado River lakes is to follow the contour of the shoreline that you are near. If it is a cliff wall above water (the Narrows as an example), it is probably a cliff wall below water, if it is a gradual downward slope above water (Boulder Beach as an example) it is probably the same underwater. The issue that most should be concerned with, and specifically mentioned by rjlipscomb, is the trickiest . . . an ?underwater mountain?.
If you look at any of the rocky points that jut out into the lake, the dry portion goes out a ways and then they often rise up to a kind of pinnacle and then drop down, extend out and then rise up again and often result in an Island at the end. These are what you need to practice my color depth method on. You can even kind of see the color differences and the effect of cloud cover in the pic above. Some of the worst ones have been marked, but again, I can see them very plainly well before I would hit them; especially with a clear sky. On a cloudy and windy day, this can be a real problem, and of course at night. On a clear day, if you hit something you have to really screw up bad . . .
Check here for the best map I have found for Lake Mead. You can trust the contours, and if you stay in the original river channels, then. . . uh . . . well 100, 200 or 300 ft. is pretty durn safe . . .
Oh, uh, anybody that sends me a bill for skeg, gelcoat or fibergalss repairs will be outed in these here forums
So here is my daily-lake-depth-confirmation-method that has kept me from hitting anything at Mead for over 20 years. This method works probably anywhere, even offshore, but I hear the concern more with Mead simply because we are down 115 ft.Looking around any part of Mead you can see the whitish stripe indicating the part of the shore that was previously underwater:
It also shows the basic color of everything underwater there . . . white. If you have a depth sounder you can confirm my method, but you can also do this by jumping in and swimming . . . While traveling along you will see the same basic color of water: a dark, greenish blue. Find any lighter shade of green and carefully float over it. Check the depth sounder. Now try the same with even lighter color shades. I do this the first day of every trip. This gives me a reconfirmation of what my eyes tell me about depth and is specific to that area?s water clarity and the sky that day. What I have found is that I can easily see "color" (lighter shade of green than the surrounding water) at 20 feet, and often 30. I can also tell the difference between 20, 10 and 5 feet if I pay attention.
There are very few spots on the entire Lake that contradict this method. Basically any weed clumps that might darken the underwater obstacle, but these are most common right near the shore and are not a legitimate concern in open water. Also, wherever the Colorado is currently dumping her beautiful, namesake mud, you can chuck any method out the window because the difference between 20 feet and 2 inches is not discernible at all
This happens to be right at Sandy Point now, but most never even see this area as it is roughly 50 miles from Echo and Callville.Also, another tip I have learned about all of the Colorado River lakes is to follow the contour of the shoreline that you are near. If it is a cliff wall above water (the Narrows as an example), it is probably a cliff wall below water, if it is a gradual downward slope above water (Boulder Beach as an example) it is probably the same underwater. The issue that most should be concerned with, and specifically mentioned by rjlipscomb, is the trickiest . . . an ?underwater mountain?.
If you look at any of the rocky points that jut out into the lake, the dry portion goes out a ways and then they often rise up to a kind of pinnacle and then drop down, extend out and then rise up again and often result in an Island at the end. These are what you need to practice my color depth method on. You can even kind of see the color differences and the effect of cloud cover in the pic above. Some of the worst ones have been marked, but again, I can see them very plainly well before I would hit them; especially with a clear sky. On a cloudy and windy day, this can be a real problem, and of course at night. On a clear day, if you hit something you have to really screw up bad . . .
Check here for the best map I have found for Lake Mead. You can trust the contours, and if you stay in the original river channels, then. . . uh . . . well 100, 200 or 300 ft. is pretty durn safe . . .
Oh, uh, anybody that sends me a bill for skeg, gelcoat or fibergalss repairs will be outed in these here forums