It's easier for us to list lakes where internal combustion engines are NOT ALLOWED:

• Lake Alice
• Ames Lake
• Beaver Lake
• Cottage Lake
• Lake Desire
• Lake Dolloff
• Lake Geneva
• Lake Holm
• Lake Joy
• Lake Killarney
• Lake Langlois
• Lake Leota
• Lake Margaret
• North Lake
• Pipe Lake
• Shadow Lake
• Shady Lake
• Spring Lake
• Star Lake
• Steel Lake
• Ronald Bog
• Lake Twelve
• Lake Walker
• Lake Wilderness
• Lake Twelve

Find King County Boating Restrictions in the King County Code under Title 12, Section 44: Public Peace, Safety and Morals, Boating Regulations.

• Speed Limit: Unless otherwise noted in the King County code, maximum boat speed is 8 miles per hour.
• Personal watercraft vessels must follow all pertinent regulations.
• ALL vessels must have at least one personal flotation device per passenger onboard.
• Boater Education Cards: Anyone born on or after January 1, 1955, must have a boater education card to operate a vessel with an engine of 15 or more horsepower.
• Powered vessels are required to remain 50 feet from swimmers when the propeller is engaged.
• Non-motorized craft have the right-of-way.
• Make sure to inspect your watercraft at the boat launch before entry and after exit to avoid spreading any invasive or nuisance aquatic plants or animals to other lakes.

More information:

• Washington State Parks and Recreation Boating Handbook (external link)
• Washington State Recreational Vessel Regulations (external link)

If a lake does not allow motorized watercraft that means that no internal combustion motor may be on the lake at all, whether or not they are being used.

• Water skiing is allowed only where speed limit exceptions make it possible.
• Watercraft must be operated by at least 2 people.
• It is unlawful to waterski within 100 yards of shore. 
• There is no towing from sunset to sunrise. 
• Floatation devices must be worn.  

Find King County Boating Restrictions in the King County Code under Title 12, Section 44: Public Peace, Safety and Morals, Boating Regulations.

• For information on which lakes are stocked visit the Department of Fish and Wildlife fish stocking webpage: https://wdfw.wa.gov/fishing/reports/stocking
• To keep track of when catchables are stocked in real-time, anglers can consult https://wdfw.wa.gov/fishing/reports/stocking/trout-plants
• To keep track of when Jumbo Trout are stocked in real-time, anglers can consult https://wdfw.wa.gov/fishing/reports/stocking/trout-plants

Landscaping

• Do not feed the geese. Human food can be detrimental to the geese’s health. Supplemental feeding will also encourage the geese to stay in an area.
• Maintain grass at a height of 10 inches rather than 2 inches. Breaking up lawns with clumps of shrubbery that block the birds’ view of approaching predators makes them less comfortable in an area.
• Replacing lawns with more environmentally friendly wildflowers is an ideal solution. Areas of neat groundcovers like creeping juniper, pachysandra, and vinca can be used to break up the expanse of lawn. They could be interplanted with daffodils for spring color and day lilies to bloom through the summer. Or they could be used to avoid mowing where flowering shrubs or trees are planted. 

Other Discouragements

• Border collies are used to drive geese from places where they are causing problems. This method has been used with some success in city and county parks.
• For an at-home remedy, sprinkle powdered grape Jolly Ranchers or Kool-Aid on the grass. Geese do not like the sour taste and they will not stay in the area.
• A store-bought harmless repellant (ReJeXITTM or Goose ChaseTM) derived from grapes is effective in keeping geese away from specific areas like golf courses, parks, and lawns because they don’t like the taste of it.
• String low wires or firmly secured (to avoid entanglement) fishing line on geese landing sites.
• Use mylar tape, flags that flash and make a noise in the wind, or noisemakers to signal danger and deter the geese.
• All of these methods are most effective if begun in the spring before geese get in the habit of grazing where they are not wanted.
  

When we think about whether a lake is safe for swimming, we usually focus on two things: toxic algae and poop in the water. Both of those can change from day to day, and not every lake is regularly tested for either. So unfortunately, we can’t give you a simple answer, but we can give you some advice on what to look out for:

• Check to see if you lake has a history of toxic algae blooms, and always look out for an algae bloom before swimming. You can go to the Northwest Toxic Algae website to learn more about toxic algae, and view the gallery to see more photos of toxic algae blooms. If you do see an algae bloom that looks like it might be toxic, please stay out of it and report it to us. 
• Poop in the water can carry a range of different germs, whether the poop is from people, pets, or wildlife. It’s not visible in the water like an algae bloom is, so we recommend you take a look and smell along the shoreline where you’ll be swimming. We also generally recommend that people not swim for two days after a summer rain that’s more than a mist. Animal poop builds up on the land during dry weather and then gets washed into the lake all at once when it rains. King County tests the water for poop at many popular public swimming beaches on Lake Washington, Lake Sammamish, Green Lake, and other lakes. For a map and list of the beaches we test the water, see the King County Lake Swimming Beach homepage. 

From May through July we typically see quite a few dead three-spined sticklebacks in the shallow waters around our large lakes and along the Lake Washington Ship Canal.

These small fish are typically minnow-sized sticklebacks or yellow perch, and the die-off is a natural phenomenon that occurs annually. The die-off is not the result of a toxic spill or other water quality problem.

May through July is the spawning season for many fish species in the lake, which is a stressful time for male and female fish that often results in the death of some individuals after the spawning period. Most of the dead fish found are males, as they expend a lot of energy in attracting the females, building the nest, and caring for the young. Fish that die after spawning are often washed up, and can be found in concentrated groups in shallow waters and on our beaches. In the Lake Washington system, many sticklebacks live for just one year, but in other places around the country they may live 2-3 years.