Riffe Lake is a massive Cowlitz River reservoir that anglers should get to know better if they like to catch lots of land-locked coho salmon and smallmouth bass.
And right now, Riffe Lake also is at least temporarily an excellent trout fishery, now that the survivors among about 400,000 triploid rainbow trout stocked in 2020 are plenty big enough to keep and in many cases are snatching coho lures before the salmon.
Unfortunately, recent reports suggest that the sheer numbers and voracious appetites of the triploid trout might be reducing forage and stunting normal growth rates for the coho, which anglers say seem to be shorter and skinnier than usual for this point in the season.
Also, WDFW and sport anglers are reporting in that the triploids tend to be full of intestinal worms, which won’t hurt you but should be cleaned out of the gut cavity thoroughly before cooking.
Riffe covers more than 11,000 acres at full pool (typically in the spring), making it the largest non-Columbia River reservoir in Washington.
Once known as Mossyrock Lake, and even as Davisson Lake, it was eventually named for the community of Riffe inundated by Mossyrock Dam in the late 1960s.
Yet despite its considerable size – over 23 miles long with more than 50 miles of shoreline – and offers excellent if sometimes under-appreciate fishing opportunities.
Coho Salmon (and Chinook)
Coho salmon are the most popular quarry at Riffe Lake, and this is one fishery that will draw fair numbers of anglers to the reservoir. However, it’s so big, once there anglers can spread out.
Riffe has become so reliable for this fishery that even some fishing guides fill up boats with customers who then fill up the boats with five-fish limits of these tasty fish
These salmon are smaller than ocean-going coho but very often reach 12 to 15 inches (and sometimes larger) and can be nearly as fat as footballs.
They also are great fighters for their size, prone to making strong runs and sometimes spectacular leaps.
An occasional Chinook will wind up in the catch, and might be a bit larger, but the coho are the bulk of salmon caught here. Some anglers will keep releasing fish to try to include a Chinook or two in their bag limit.
Some anglers mistake coho for kokanee. The Washington Department of Fish and Wildlife and Tacoma Power report that there are no kokanee salmon in Riffe, although some anglers swear that remnants of these land-locked sockeye still exist in the reservoir.
The salmon here are the product of WDFW’s program of trucking mature hatchery salmon into the Cowlitz River system upstream from the dams.
Those fish spawn upstream, and then their young migrate downstream. If they get past the fish collector at Cowlitz Falls Dam (Lake Scanewa) upriver, it’s a very short swim to Riffe, where they are stopped by Mossyrock Dam and turn the big reservoir into their mini ocean.
If you show up at the right time of the year with a boat capable of plying the big lake and play this right, you have a good shot at catching good numbers of freshwater salmon.
The best coho fishing here tends to be from mid-spring to early summer, and for good reason.
For one, the coho tend to run much closer to the surface of the lake, where they can be caught more easily.
And, maybe more importantly, this time of year the bulk of your catch will be second-year coho, which tend to be at least 12 inches and often better.
If you come in the hot mid- to late summer, you’ll likely need to fish in water up to 100 feet deep, which means employing down-riggers or a ton of weight.
Also, by that time of the year, most of your catch will be the younger class of fish, which are roughly the size of just-legal stocked rainbows. And you can catch those just about anywhere.
Trolling catches a lot of land-locked salmon at Riffe.
An effective and common approach here is similar to the techniques for trolling for trout or kokanee elsewhere.
Troll with a flashy attractor (a set of blades or a dodger) ahead of bait or lures.
The go-to baits are nightcrawler (or a piece), corn and shrimp, or combinations of two of the three, according to Lip Rippers Fishing Adventures.
Lots of anglers also troll with lures. You can combine some lures with or without bait, such as Wedding Ring spinners or hootchies. Other lures sometimes fish best without bait, including spinners, spoons and wobbling lures like bright FlatFish.
Still-fishing also is a good way to catch coho, and is especially popular for bank fishing near the dam and up at the fishing bridge at Taidnapam.
Use the same types of baits for still fishing. Often, shore and boat anglers suspend the bait several feet beneath a bobber when the fish are still running shallow enough.
Find more places to go salmon fishing in Washington and also pick up some tips to catch more salmon in our simple how-to fishing guide. Also, definitely check out the top-tier salmon and steelhead fishing in the Cowlitz River below Mayfield Dam.
Smallmouth Bass (and Largemouth)
The other potentially great fishery here is for smallmouth bass, which are available in good numbers and can reach trophy sizes in the 5-pound range or better, which is a very nice smallmouth in the Pacific Northwest.
Former bass fishing guide Roger Luce told us that Riffe Lake is one of his preferred fishing spots for big smallmouth bass in Washington, along with the Columbia River.
Smallmouth bass are savage hunters that feed on crayfish, smaller fish and other prey that comes their way.
On the hook, especially on light tackle, smallmouth are strong fighters for their size.
Soft plastics, crainbaits, spinners, and other lures will catch smallmouth bass. Worms and nightcrawlers also are effective bass baits, but note that if you are practicing catch and release fishing, bait-fishing is riskier because more fatal hookups occur.
Smallmouth bass love rocky and hard-bottom structure but will use all types of structure. They’ll stage and hunt off shorelines, points, drop-offs, stumps, rock-face dams and other spots.
During the spring spawning period, smallmouths often can be found in very shallow waters and also will move into some cove areas, like the little lake fingers where small tributaries come into the reservoir.
After spawning and as the waters warm, smallmouth bass are likely to move into somewhat deeper water but will still be relatively high in the water column, probably in 10 to 20 feet or less in most cases, although bright mid-day sunlight may push them deeper.
You won’t find smallmouth bass at depths of 100 feet, like the late-summer salmon.
Riffe also has some largemouth bass, although reports from the reservoir suggest this is a smaller fishery than the smallmouths these days.
For one, Riffe runs cold and smallmouths are native to more northerly climates than largemouths.
However, largemouths do have the potential to grow a bit larger than smallmouths in the Northwest.
If you are specifically trying to find largemouth bass at Riffe, we’d suggest trying out some of the shallower cove areas where the water is a little warmer. You still may end up catching more smallmouth than largemouth.
More: Bass Fishing: Simple How-To Techniques and Tips
Trout Fishing
Unlike the reservoirs in either direction, Riffe isn’t typically managed as a trout fishery.
As mentioned, the lake is currently home to lots of triploid rainbow trout that were stocked when a private aquaculture company found itself without means to raise them as expected, so Tacoma Power accepted hundreds of thousands of the young fish in 2020.
Reports in 2021 so far are that the sterile rainbow trout have grown into nice keepers and some days are hard to keep off the hook if you are specifically targeting the coho. (Try going deeper for the coho, but you’re still likely to get a mixed bag.)
In other words, for a year or two anyway, Riffe Lake has excellent rainbow trout fishing. For now, the rainbows are similar in size to the coho. By 2022, we would expect fewer but larger trout here.
Outside of this triploid trout bonus, Riffe has not been on the trout-stocking plan, but there have been three species of trout caught in the reservoir anyway.
In typical years trout were caught more incidentally than on purpose by anglers fishing for more numerous land-locked salmon, and at least some drop down from the Cowlitz and tributaries.
Every great once in a while a really big brown trout is taken here (anglers report 10-plus pounders), and there also are scattered numbers of rainbow and cutthroat trout.
The browns of any size are not here in volume, but they’ll occasional hit a trolled lure, some bait, or even a bass crankbait.
If you are targeting the browns, try using lures that imitate smaller fish, which are a favorite brown trout forage.
Also, browns are night feeders so you’ll have a better chance during lower-light conditions.
If you’re specifically after rainbow trout in this area, keep Mayfield Lake just downstream and Scanewa Lake just upriver on your radar. Both of those are stocked with large numbers of hatchery rainbows each year.
But Riffe typically does have some rainbows that likely drop in from the Cowlitz and possibly a few from stockers put into Rainey Creek at the northeast end of the reservoir.
Also, WDFW plants steelhead upriver along with the salmon to spawn, and their young also can find their way into Riffe the same way the young coho and Chinook do.
Coastal cutthroat trout also are native to the Cowlitz and its tributaries and occasionally make their way into the reservoir, where they can be caught to nice size.
The wild cutthroats and browns are targeted by a minority of anglers, but if you try this we suggest you work the waters near the mouths of incoming tributaries, particularly at the eastern (upper) end of the reservoir.
Usual trolling and bait-fishing techniques will catch trout when you can find them, but again the best approach is probably to come to Riffe for the coho and pick up an occasional trout.
Catfish and Panfish
Bullhead catfish also are available in good numbers and decent sizes at Riffe, and actually taste better than you might think from these cool waters.
Bullheads are typically in relatively shallow water, usually within casting distance from the shoreline.
Bullheads often will like siltier bottoms found in coves and shallows.
Like other catfish, these fish are easily caught on bait whenever you locate them. Nightcrawlers and any types of worms, cut-baits like fish or shrimp, chicken livers, prepared catfish doughs (“stink baits”), and many other baits will all do the job.
Read up on the best catfish fishing baits and techniques.
Riffe also has modest fisheries for crappie and bluegill, although it runs pretty cold for fishing for these species to be exceptional. But you might find a spot where either is biting.
Bluegill prefer small natural baits but also hit artificial flies and small lures.
Crappie like lures that imitate very small fish. Crappie jigs look like shaky minnows and are the most common lure deployed, but very small crankbaits, spinners and other lures also catch them.
Honestly, if you’re looking for crappie, bluegill, largemouth and even channel catfish (as well as stocked trout in the spring), consider neighboring Swofford Pond.
Access and Facilities
Despite being well over 20 miles long with tons of shoreline, bank access isn’t as good as you might think.
It’ll take some serious scrambling to reach water in many spots, especially in big middle of the lake.
However, there are decent spots to fish from shore at both ends of the dam on the west side and at and Taidnapam Park at the upper (east) end of the reservoir, where there also is a fishing bridge.
Mossyrock Park also has shoreline access but it’s not as popular for catching salmon from the shore right there as it is for boaters heading out onto the lake.
The Taidnapam Park fishing bridge is at the very upper end of the lake, where the Cowlitz River enters. It runs parallel to the vehicle bridge for Champion Haul Road.
This is a fun experience, even just to watch.
Anglers, usually after the land-locked coho but occasional catching other salmon or trout, dangle baits down into the water some 40 feet below.
When they hook a fish, the goal is to get that fish straight up as fast as is safe without the fish coming loose and dropping back into the lake. Anglers don’t always have the upper hand.
Overall, boaters have a clear advantage in a huge water like Riffe Lake, with a good ramp at Mossyrock Park on the southwest end and more launches around Taidnapam Park and Kosmos on the east end.
As the water levels drop toward late summer and into fall, the east end ramps at Kosmos and Taidnapam tend to become inaccessible.
The long ramp at Mossyrock Park is accessible except in the lowest-water conditions.
You can check Tacoma Public Utilities’ access page for current access at Riffe and its other recreation areas.
Mossyrock Park has lots of camping and day-use amenities in addition to the reservoir’s best west-end boat launch. It’s a popular spot in the summertime.
At the upper (east) end of the reservoir, Taidnapam Park includes a very popular campground that often requires reservations well in advance. If you want easy access to bank, pier and boat fishing, this is a spot to consider.
From Interstate 5 near Napavine, expect the drive to Riffe to be between 30 minutes and an hour heading east on Highway 12 past Mossyrock, depending on which part of the big reservoir you go to.
It’s more like an hour and a half from Tacoma, taking Highway 7 south to Morton located north of mid-lake, and then Highway 12 to whichever end of Riffe you plan to fish.
Find more fishing spots in Lewis County
Washington Resources
WDFW Fishing and Stocking Reports
WDFW Fishing Regulations
National Weather Service forecasts