Swinomish Channel Navigation

Swinomish Channel Currents at La Conner
Rules of Thumb:
To help you predict slack water and current direction at La Conner – the actual time of slack water and duration of current flow are dependent on the range between high and low water, and are affected by river runoff (from the Skagit River). Approximate is the best you can get.

Use Seattle Tides and add 30 minutes in addition to any adjustments for daylight:

  • Slack water occurs 2.5 – 4 hours after high or low water at Seattle + 30 minutes
  • Current flows north 2.5 – 4 hours before high water to 2.5 – 4 hours after high water
  • Current flows south 2.5 – 4 hours before low water to 2.5 – 4 hours after low water
  • You can also check the current arrow at the La Conner Landing fuel dock – it’s just to the left of the front door and is changed as soon as the current changes.

Bridge Clearance:

  • The Rainbow Bridge has a 75’9” clearance (the cables have a 72′ clearance)
  • The Twin Bridges bridge has a 75′ clearance

From the North – Bellingham (20 miles)

Williams Point (Chart 18424)
SE Point – Guemes Island (Chart 18427)
Swinomish Channel ”

From the West – Friday Harbor (18 miles)

Upright Head (Chart 18434)
Thatcher Pass (Chart 18429)
Guemes Channel (Chart 18427)
Swinomish Channel ”

From the South – Everett (33 miles)

Camano Head (Chart 18443)
Saratoga Passage (Chart 18423)
Skagit Bay (Chart 18427)
Swinomish Channel ”

Navigation

Paying attention to the tides can help you estimate the time of slack water and duration of current flow in the Swinomish Channel at La Conner. Because it’s dependent on the range between high and low water, and is affected by river runoff, the time of slack current can only be estimated. There are a couple of ways to do this.

The tugboat operators base their estimate on the tide tables. Slack water at La Conner Landing occurs between 2 and 3.5 hours after high or low water. For example, if High Water at La Conner occurs at 5 a.m., slack will be sometime between 7 a.m. and 8:30 a.m. at periods of a minor tide change, the slack will occur closer to 2 hours after the predicted high or low. When there is a large change in tide, the current turns almost 3.5 hours later. The current flows north for 2 to 3.5 hours before high water until 2 to 3.5 hours after high water; it flows south for 2 to 3.5 hours before low water until 2 to 3.5 hours after low water.

The 1.5-hour leeway leaves a lot of room for guessing, and some local boaters prefer to use a different method as their guide. Slack water occurs when the high water drops 2 feet. Similarly, low water slack occurs after the low water has risen 2 feet. When the tide change is less than 2 feet, one can expect an accordingly small amount of current.

When running during low tides in the southern part of the Swinomish Channel, boaters should favor the east side of the channel from the southernmost house in the Shelter Bay Community to the entrance of Shelter Bay itself. There is a rock wall breakwater on the east side, which should be favored. The western 2/3 side of the channel is very shallow from sediments deposited by the nearby Skagit River.