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Lake Mead National Recreation Area
Scuba
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Invasive Mussel Found at Lake Mead Live quagga mussels (a nuisance invasive species closely related to, and commonly referred to as zebra mussels) were discovered in Lake Mead on January 6 at the Las Vegas Boat Harbor marina. In order to not spread the mussel to Lake Mohave and other bodies of water, please follow the suggestions below. Effective ways boaters (including personal watercraft, canoe, and kayak users) and fisherman can ensure that their boats, vehicles, trailers and other equipment do not become the means of infecting other waters: - Drain the water from your motor, live well, and bilge on land before leaving the immediate area of the lake.
- Flush the motor and bilges with hot, soapy water or a 5% solution of household bleach.
- Completely inspect your vessel and trailer, removing any visible mussels, but also feel for any rough or gritty spots on the hull. These may be young mussels that can be hard to see.
- Wash the hull, equipment, bilge and any other exposed surface with hot, soapy water or use a 5% solution of household bleach.
- Clean and wash your trailer, truck or any other equipment that comes in contact with lake water. Mussels can live in small pockets anywhere water collects.
- Air-dry the boat and other equipment for at least five days before launching in any other waterway.
- Do not reuse bait once it has been exposed to infested waters.
Additional information can be found at the and .
General Diving Conditions Lake Mead National Recreation Area, which includes Lake Mead and Lake Mohave, is a unique freshwater diving area. It offers a wide variety of diving environments for both novice and advanced divers. The degree of visibility on both lakes fluctuates throughout the year. During the cool winter months, October to April, visibility is usually good (20 feet to 50 feet). During the summer months, May to September, algae growth is stimulated by warmer water temperatures that results in reduced visibility (30 feet to less than one foot, depending on location and depth.) Visibility also varies with depth: the deeper one goes, the darker it gets. This is particularly pronounced in the summer months when the thermocline formed by warmer surface waters is present. During the summer months the first distinct thermocline usually occurs near the 30 foot to 40 foot depth. From surface level to 30 feet in depth, the temperature may range from 70° to 82° Fahrenheit, and this layer supports the majority of algae growth. The second distinct thermocline usually is found near the 60 foot depth. Between 30 feet and 60 feet the temperature ranges from 70° to 60° F with less algae present due to cooler water. Below 60' in depth, the water temperature is 60° to 52° F. At this depth, the water is usually clear but much darker in summer than in winter due to the dissipation of the light caused by the presence of algae in the warmer water above. During the winter, there is usually no thermocline with the entire water column in the low 50 degrees. There are several exceptions. Where rivers or streams flow into Lake Mead, visibility is poor year round due to high silt content or excessive algae growth. Examples are: Iceberg Canyon where the Colorado River flows into Lake Mead; north of Overton Beach where the Virgin and Muddy Rivers flow into Lake Mead; and Las Vegas Bay near the terminus of Las Vegas Wash. The reverse is true, however, from Hoover Dam to mid-way between Willow Beach and Eldorado Canyon. The colder water released from Hoover Dam (52-55 degrees F) provides clear water and good visibility throughout the year. Most of the currents in Lake Mead and Lake Mohave are slow and undetectable. From Hoover Dam to mid-way between Willow Beach and Eldorado Canyon, however, the current ranges from 3 to 12 miles per hour. This current is variable depending on the volume of water released from Hoover Dam and the water level in Lake Mohave. At Ringbolt Rapids, the speed of the water may reach 16 miles per hour on week days. Navigational and cove name maps are available at Alan Bible Visitor Center and all marinas. There are dive shops in Boulder City and Las Vegas, Nevada, and Bullhead City, Arizona, which supply equipment sales and rental, instruction, and air. Check the local telephone directory. Return to Top
Restricted Areas Lake Mead - the following are areas closed to diving: - Above and below Hoover and Davis Dams.
- The portion of the Lower Overton Arm of Lake Mead, from a northern boundary at approximately Latitude N. 36° 15' to a southern boundary at approximately Latitude N. 36° 10', and from the western shoreline to the eastern shoreline, to be closed to SCUBA and all forms of underwater diving unless a permit has been issued by the Chief Ranger's office.
The restriction is necessary to protect a sensitive archaeological resource, the submerged B-29 aircraft, while the National Park Service completes a resource protection plan for the area. The B-29, and the site upon which it rests, are managed by the National Park Service under the National Historic Preservation Act. Permits for scuba diving in this area may be obtained by contacting the Chief Ranger’s Office at 702.293.8908. Each application will be considered on a case-by-case basis. - All designated boat harbors. Divers employed by concessioners diving on official business and special events approved by the National Park Service are exempt from this restriction.
- Designated swim areas.
- Southern Nevada Water Project water intake tunnel and the water intake overhead boom, located on the east side of Saddle Island, just north of Lake Mead Marina and Boulder Harbor.
NOTE: The suction in the tunnel is not dangerous at normal water levels (a maximum of 2.6 miles per hour, 585 cubic feet per second at the tunnel entrance), but with all 20 units operating, a possible suction hazard could be present at low lake levels. The top of the tunnel is at 1,050 feet above sea level, and the entrance is 12 feet in diameter with a vertical bar screen with six-inch spaces between bars. At average lake levels, the tunnel is about 110 feet below the surface. Lake Mohave - the following areas are closed to diving: - Above and below Hoover and Davis Dams.
- All designated boat harbors. Divers employed by concessioners diving on official business and special events approved by the National Park Service are exempt from this restriction.
- All designated swim areas.
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Potentially Hazardous Areas Lake Mead - Iceberg Canyon and uplake: soft, viscous silt layers on bottom several feet thick. The further uplake you travel, the muddier the water becomes due to the silt content of the Colorado River. Also, the thermocline is usually found at a depth of 5-l0 feet with the water temperature dropping to the low 50 degrees.
- Ski Beach and Personal Watercraft Beach near Hemenway Harbor: excessive boat traffic, especially from Easter to Thanksgiving.
- Gypsum ledges, which have been eroded by wind and water, may have unstable overhangs.
Lake Mohave (up to 17 feet annual vertical fluctuation) - From Hoover Dam to Chalk Cliffs (22 miles): narrow channel and heavy boat traffic.
- Ringbolt Rapids (8 miles north of Willow Beach): swift and turbulent water up to 16 miles per hour, depth to 70 feet. Recommended for ADVANCED DIVERS ONLY.
- Katherine Landing area: heavy boat traffic.
Safety Tips - Due to years of rod and reel fishing, areas containing submerged brush and trees are usually laced with pieces of monofilament line and hooks. Entanglement can be serious, so always carry a dive knife with you while diving.
- Never dive alone. Use the "buddy" system.
- Fly the standard red and white diving flag within 100 feet of diver while diving. A floating tow flag is essential in many areas due to heavy boat traffic.
- Plan your dive; dive your plan.
- Do not dive beyond the capability of the least experienced member of your group, and do not dive unless trained and certified.
- Check with the local area rangers on the latest weather forecasts. (Weather Page) All launch ramps have weather boards.
- The nearest recompression chamber is located at the University Medical Center (UMC) in Las Vegas so it is imperative that the U.S. Navy dive tables and altitude conversions be followed. In recent years, Lake Mead's elevation has between 1140 to 1170 feet above sea level. Lake Mohave's elevation fluctuates between 630 feet and 647 feet above sea level.
- It is essential the following information be given to the ranger and doctor when a diving emergency occurs:
- Depth, bottom time, and surface intervals of all dives within 12 hours.
- Conditions of ascent; breathing, non-breathing, conscious, etc.
- Names of others in the dive group, especially the victim's dive buddy.
- Signs and symptoms of victim, and time symptoms appeared.
- First aid administered to victim.
NOTE: Standard first aid for an embolism or decompression sickness is to give oxygen, if available, and lay the victim down on his left side with his head slightly lower than the body. Return to Top
Preferred Dive Locations Lake Mead - Castle Cliffs-Gypsum Reef: good drop-offs, large gypsum and sandstone rocks, visibility variable. Access by boat.
- Kingman Wash: gentle slope, good for novice divers, occasional heavy boat traffic, visibility variable. Access by boat.
- Black Canyon: sheer wall diving, depth 500 feet, usually good visibility. Access by boat.
- Boulder Islands: large cement tank used during construction of Hoover Dam to store water, located off tip of "Big Boulder Island," visibility variable, often heavy boat traffic. Access by boat. Also, two 45 foot to 50 foot vessels have been placed on the bottom for fun and training. (Tortaga and Cold Duck).
- Dive Park (North Boulder Beach): just north of the designated swim beach, gentle slope to 70 foot depth, good training site, visibility seasonally fair to good. Access by vehicle or boat. Boat traffic restricted to dive support vessels. Also, five to ten vessels or other objects have been placed on the bottom for fun and training. Objects are marked with yellow buoys and range in depth from 30 feet to 70 feet.
- Saddle Island: west side of Saddle Island (Boulder Harbor side) moderate drop-off, excellent area for freshwater clams in 40-60 feet of water, visibility variable. Access by boat preferable.
- Wishing Well Cove-Boulder Canyon: excellent location with steep drop-offs, narrow canyon, canyon bottom stair steps from 0-140 feet, usually good visibility. Access by boat.
- Gypsum Reefs-Virgin Basin: extensive white gypsum reef area with irregular underwater erosion forms, visibility variable. Note: outstanding eroded formations may present unstable overhangs. Access by boat.
- Cathedral Cove: about 5 miles south of Echo Bay, protected water, usually good visibility, interesting underwater formations. Access by boat.
Lake Mohave - Black Canyon: moderate to swift water, usually good visibility, water temperature 52-55 degrees F all year, steady boat traffic, excellent current drift diving conditions. Access by boat.
- Ringbolt Rapids: advanced divers only, swift and turbulent water for about 100 yards, visibility usually only fair due to turbulence and bubbles, 50-70 foot depression at base of rapids. NOTE: Hand-held buddy line and surface support boat essential. Boulders and rock formations may pose a hazard along canyon walls. Access by boat. The high water flows and boulders along with other obstructions make Ringbolt Rapid a potentially hazardous dive along the Nevada side. AVOID THE NEVADA SIDE.
- Work Barge: located 4¼ miles below Hoover Dam on the Arizona side. The 38 foot tow barge was used on the spillway tunnel repair project and sank in 1946. It is located in about 25-35 feet of water in moderate to swift current. The barge is protected under the Antiquities Act, therefore, nothing may be removed or damaged. Access by boat.
- Cabinsite Point (north of Katherine Landing): vessels prohibited. Two boat wrecks. Access by vehicle.
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Aquatic Life Regulations - Nevada and Arizona State fish and game regulations are in effect. A combination Nevada/Arizona fishing license is required. Spearfishing is legal for carp and striped bass ONLY.
- Spearfishing for striped bass is permitted throughout Lake Mead but only from the cable below Hoover Dam to Cottonwood Cove on Lake Mohave. Spearfishing is prohibited within 1/2 mile of any dock or swimming area.
Fish - the following species of fish may be found in the two lakes: - Largemouth Black Bass: During the spring and summer they can be observed guarding their egg nests or schools of fry. During this period their behavior is aggressive. (No spearfishing)
- Striped Bass: impressive silver fish seldom seen by divers. Up to 50+ pounds. Legal to spear.
- Channel Catfish: average 4 pounds. (No spearfishing)
- Black Crappie: average one pound. (No spearfishing)
- Rainbow Trout: up to 5 pounds in Lake Mohave. (No spearfishing)
- Razorback Sucker: usually found only in Lake Mohave. Under federal law, it is classified as an endangered species, and is one of the few remaining original Colorado River residents. (No spearfishing)
- Bluegill Perch: found in shallow waters around rocks and vegetation. (No spearfishing)
- Green Sunfish: found in shallow waters in rock holes and cracks, very shy and colorful. (No spearfishing)
- Threadfin Shad: about 3 inches, the predominate "food" for game fish, usually found in large schools.
- Carp: up to 20 pounds, legal to spear.
Other Aquatic Life - Crayfish: found in heavy bottom vegetation, rarely seen.
- Asiatic freshwater clam: found in abundance in both lakes. Legal to collect.
- Freshwater sponge.
- Eel Grass: usually found above Willow Beach on Lake Mohave, often grows to 15-20 feet long, undulating in the current.
- Algaes, growing or hanging from submerged bushes and trees, are often found hanging on strands of monofilament fishing line.
- Soft shell turtles
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Emergency Procedures - Contact the nearest Ranger Station or Park Ranger on duty, or
- Telephone the National Park Service 24-hour Communications Center at 702-293-8932 or 1-800-680-5851 and they will notify the nearest Park Ranger. The Communications Center also monitors Marine Band emergency channels 16 and 22.
- Area Ranger Stations are manned intermittently; therefore, the following numbers should be used for information purposes only.
Overton Beach (702) 394-4021
Echo Bay(702) 394-4060
Callville Bay(702) 565-9612
Las Vegas Bay(702) 565-8368
Boulder Beach(702) 293-8904
Temple Bar(928) 767-3401
South Cove(928) 564-2220
Willow Beach(928) 767-4000
Cottonwood Cove(702) 297-1229
Katherine Landing(928) 754-3272 Return to Top
Recompression Chambers Primary Chamber University Medical Center (UMC), information phone and emergency 24-hour phone number 702-383-3603 (diving physician is always on call) or call 911 and await transport by ambulance to the emergency room in Las Vegas. Back-up Chambers University of California, Catalina Island chamber, Emergency phone 310-510-1053. information phone 213-743-6793 (Mon-Fri), Call the Medical Alert Center, Los Angeles, 213-221-4114. They will contact the U.S. Coast Guard and Catalina chamber and will make all pre-arrival arrangements. Fly direct to the Los Angeles International Airport, where the U.S. Coast Guard helicopter will pick-up and deliver to Catalina. San Diego
Call the San Diego County Lifeguard Service, 619-224-2708, and they will handle the local arrangements and proper notification. - University Medical Center Life Flight Emergency Number 619-543-3683
- USS McKee United States Sub-Tender (Don Ingram) Tender - 619-224-2735 Submarine Flotilla Operations - 619-225-6818
REMEMBER: Whenever a diving accident victim goes to a chamber for treatment the following information is necessary: - Victim's full name and age.
- Victim's symptoms and treatment administered after discovery.
- Profile of dives, depths and bottom times during past 12 hours before accident.
- Depth and bottom time of last dive (or during dive) before accident.
- Brief description of accident and names of witnesses.
- Flight number or airline, estimated time of arrival and airport. Include airplane's pressurized altitude if possible. (If using the back-up chambers in California)
For questions regarding diving accidents you may contact the Divers Alert Network (DAN) at 800-446-2671 or 919-684-2948 (Monday through Friday) or the emergency number at 919-684-8111 (Monday through Friday). Return to Top
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