Coeur d’Alene Lake

The pristine setting of Coeur d’ Alene Lake and it majestic surroundings make it one of the most beautiful lakes in the world.  Coeur d’Alene Lake covers more than 30,000 surface acres, is 26 miles long, varies from 1 to 3 miles wide and has 109 miles of shoreline.

Coeur d’ Alene is a glacier formed lake whose depth was increased by the construction of the Post Falls Dam in 1906.  The dam is now owned and operated by Avista Utilities for hydroelectric generation, flood control and irrigation.  The water level of the lake is controlled naturally during the summer season, then  Avista Utilities drops the level in the fall to create storage capacity for spring snow melt.  The Coeur d’Alene Tribe owns the southern third of the lake.  The EPA has ruled that the Tribe may set its own water-quality standards on its portion of the lake.

Sources for the lake include the St. Joe, St. Maries and the Coeur d'Alene Rivers.  The lake flows outward through the Spokane River where it flows for 25 miles into east central Washington.

HDB Marine – 32 years experience on Coeur d’Alene Lake

Our headquarters is located at the mouth of the Coeur d’Alene River by Harrison, ID.  We have been building docks here for twenty-eight years.  Following are some observations about dock construction on Lake Coeur d’ Alene that may be of value to you.

Design Considerations on Coeur d’Alene Lake

Coeur d’Alene and its rivers have a diverse range of bottom conditions/materials, water depths, wave and wake environments, currents, spring debris issues.  We consider each of these factors when developing a  Purpose Driven Design for HDB customers.

Bottom Conditions/Materials – anchorage options

  •  Mud, Sand & Clay – driven pile anchors, wood pilings 
  •  Gravel, rock – driven pile anchors, steel pipe piles 10” – 12” diameter or custom
  •  Rock bottom – Cable & Chain with  concrete mass anchors

Water Depths

  • Will the dock be aground during the 7’ winter draw-down? – plan accordingly,    consider winter storage
  • How will spring flood ( + 8’ ) affect the site? – will dock still be accessible, what is proper pile length, will fixed pier dock be submerged?

Wave & Wake conditions

  • Sites with frequent 3’ plus wave conditions require special design considerations
  • Frequent wake conditions – will floating dock be constantly moving/undulating? Is fixed pier dock more user friendly for dockside leisure activities?


  • Is site subject to heavy currents and debris flow in the spring season? - debris defector, winter storage
  • Design dock so that boat is moored with bow facing the current – better for debris reflection and boat handling

Coeur d’Alene Areas & Conditions 

St. Joe, St. Maries and Coeur d’Alene Rivers:  These rivers have mud, sand & clay banks – have strong currents in the spring – are subject to heavy debris flow during spring melt off – subject to spring floods up to + 7 feet and have current year around.  The dock of choice is the HDB Cedar Log Dock anchored with long wood or steel pilings.  Design preference is to design the dock so that the moored boat faces upstream. 

Spokane River:  Has a hard river rock bottom. Steel pilings are preferred for their ability to better penetrate the bottom.  The two most popular dock designs are Fixed Pier and Floating Docks.   Fixed Pier docks with bottom mounted boat hoists are the best choice for sites with heavy boating traffic (wakes) as the fixed dock offers a stable platform that is not affected by boat wakes.