Young Alex Harrington likely won’t ever forget his sparkling bright Lake Washington cutthroat. Trolling with a downrigger is one of the most effective ways to catch big trout here. Photo by Terry Wiest

Lake Washington is like a big, bright diamond that reveals its shiny facets to those willing to work a little for their fish. Angle Lake, hard next to Seattle-Tacoma International Airport, is more like a gem where you can fish under the airplanes and take a break to barbecue your catch. Then there’s Green Lake, a precious stone set in the Emerald City that serves as its urban outdoors retreat.

All of these fishing destinations ringing Seattle offer excellent trout fishing. Here’s how to capitalize on the urban bounty.

LAKE WASHINGTON
Lake Washington, lying in a deep, narrow trough gouged by the Vashon ice sheet millions of years ago, is now home to 28 resident and anadromous fish species, including a surprisingly large population of resident cutthroat trout. As recently as 1978, cutthroats were not even listed in the lake’s top 12 fish species. New studies reveal that cutts have replaced the northern pike minnow as the lake’s predominant big-dog predator.

How big is the dog on the porch? A few years back, one angler landed a 14.9-pounder, Washington’s biggest coastal cutthroat trout in the last 40 years. Fish that size are rare, but both rainbow and cutthroat trout run in the 3- to 6-pound range. Not bad for a lake once thought to be dying from pollution and now surrounded by more than a million people!

A map of Seattle shows how Lake Washington dominates. From Kenmore in the north to Renton at the southern edge, the lake spans 18 miles, covers 18,000 surface acres and is crossed by two floating bridges carrying tens of thousands of vehicles daily to and from Microsoft. Along with numerous smaller feeder creeks, its two major tributaries, Sammamish and Cedar Rivers, at the north and south ends, respectively, dump both water and trout into the lake.

Fishery studies indicate that trout enter the lake as 2-year-olds, hang in the shallows during cool-water times, then during the summer months move into either deeper water or back into the tributaries. As fish grow larger, their preferences for location and food change -- which dictate where and how successful fishers score.

Lake Washington trout, particularly cutthroat, reveal a decided dietary preference for omega-3 oils, which they get from chomping sockeye fry and sockeye pre-smolts. Their other preferred baitfish are longfin smelt and three-spine sticklebacks, also in abundance throughout the lake.

Once cutthroats grow longer than about 15.75 inches, 98 percent of their diet is fish, according to stomach sampling data. And they eat farther away from shore, most often in deeper water. Given this information, certain catching tactics leap to mind.

A good rule here is the old saw that “Seventy percent of any body of water is fishless, so focus on that other 30 percent.” Productive trout locations include the north and south sides of both floating bridges, Juanita Point in the north, the mouth of the Cedar in the south and both ends of Mercer Island. Baitfish also orient on underwater points, so check out Dabney, Evergreen and Groat points. Two good references are DeLorme Washington Atlas and Gazetteer and the Lake Washington/Banks Lake map published by the Fish-n-Map Company (FishnMap.com).