With the fishing season on the Spokane River coming to a close this week (last day is Friday March 15th and it will re-open on May 25th), we headed out to get in one last float. The weather was narsty on Sunday: clouds, cold, rain, wind...all perfect for throwing streamers. We decided to float an upper section of the river and originally wanted to launch just downstream of Upriver Dam, but construction for the North Spokane Corridor around the Greene Street Bridge made that particular spot a no-go to float through. So, we cut the float in-half and launched at Upriver Park. There's not a boat launch at Upriver Park, but we easily managed to carry our raft a short distance and then slid it down into the river. The Spokane was discharging at around 7800cfs and the water temps were right at 40F.
Once on the river, the winds picked up considerably, so much so that back rowing wasn't even necessary and I sat with the oars tipped up out of the water. That gave us plenty of time to cast streamers into any prime spot as we lethargically drifted downstream. Chad Triplett, who is joining as our newest guide, was using a sculpin pattern on a sink-tip line when he connected with a brute of a brown trout. Below the Spokane Falls, brown trout are exceedingly rare but you can still come across them on the upper stretches of the river. We drifted for a while and Chad fought the fish into the net which absolutely made our day...that's just some stellar urban fly fishing right there!
We eventually floated down to the take-out at the Trent Avenue Bridge and again had to carry the raft a short ways to the trailer. The wind and rain were really rolling in by that time so it was great to have a short few hours on the river tossing streamers amongst the willows and other large woody debris.
The Spokane Riverkeeper's 2024 Community Science Project is off to a great start, and a huge thanks to all the volunteers that are taking part with helping to measure sediment pollution in the river and Hangman Creek (Latah Creek). Sediment is an incredibly harmful, if not the most harmful, pollutant in waters within the United States. Yes, plain old sediment (sand, silt, clay, etc.) causes immense damage to waters like the Spokane River, and that's not even talking about how it can warm the water up more quickly or looking at all the other stuff that ends up flowing into the water with the sediment (e.g., herbicides, nitrogen, phosphorus, neonicotinoid pesticides, etc.).
Excessive sediment in Hangman Creek comes from places where vegetation has been stripped and removed from the landscape which increases erosion and causes silt and fine sand to flow into the river. Sediment coming into the river is definitely not abnormal, but it is the quantity and quality of sediment that is coming into Hangman Creek that is very unnatural. This sediment not only does intense damage to Hangman Creek but it then flows into the Spokane River and causes further harm to fish and macroinvertebrates. Now, I'm not an expert on what damage sediment can do to aquatic ecosystems, but there is an excellent book by Dr. Thomas F. Waters called Sediment in Streams: Sources, Biological Effects, and Control where he details out many of the issues with sediment in rivers and streams:
Three specific effects of sediment on salmonid redds have been recognized: (1) filling of interstitial spaces in the redd by depositing sediment, thus reducing or preventing further flow of water through the redd and the supply of oxygen to the embryos or sac fry; (2) smothering of embryos and sac fry by high concentrations of suspended sediment particles that enter the redd; and (3) entrapment of emerging fry if an armor of consolidated sediments is deposited on the surface of the redd. (Waters, p. 86).
In other words, the sand, silt and clay suffocate the nesting beds (redds) of species such as our wild and native redband trout. Many of the redds on the Spokane River are located downstream of Hangman Creek and year-after-year they are covered up by excessive sediment and the eggs are killed.
We also have to look at the effects of sediment on invertebrates (the primary food source for many of the fish in the Spokane River):
The vitality and health of stream invertebrate populations is tied extremely closely to the particle size of streambed sediments. A change from gravel and cobble riffles to deposits of silt and sand results not only in a precipitate decrease in populations of those invertebrates most important as fish foods, but also a change in species from those inhabiting the interstitial spaces of larger particles to small, burrowing forms less available to foraging fish. (Waters, p. 76).
Not only does excessive sediment suffocate fish eggs, it also changes the benthic (i.e., the bottom of a body of water) population of aquatic invertebrates. Populations of invertebrates can become less dense and the species changes. Certain species of stoneflies, caddis, and mayflies need cobble and gravel habitats to survive and thrive, and when that habitat is covered over with sand those insects can no longer live there. Other species of invertebrates can move in to that sandy habitat (like worms and chironomids, and certain burrowing mayflies), but these species are much less available as a food source to the fish in the Spokane River.
Redband trout in the river have evolved to feed on insects drifting through the current, and those insects are the ones that live in the rocks and become dislodged as they are crawling around on the gravel and boulders. If the insect population changes to species that burrow into the sand, those bugs are not going to easily become dislodged and float downriver (not until some of them start migrating out of the substrate and through the water column to hatch, and only then the feeding window is very short for fish to take advantage of). As populations of aquatic insects decrease and change, the number of wild and native fish (redband trout, largescale suckers, northern pikeminnow, mountain whitefish) in the Spokane River diminish as well.
You should go check this out yourself, just walk the Centennial Trail just north of People's Park to an overlook here. On days that Hangman Creek is really flowing, you'll see the river running turbid, and all that mud is causing populations of fish and insects to decrease. Whenever I am guiding, clients inevitably ask why there are so few fish in the river because it looks so clean! The answer is complex, it's death by a thousand cuts, but one of the biggest slashes comes from the sediment pouring out of Hangman Creek.
Washington state has a standard for how much sediment a river or stream can have in it (i.e., its turbidity level) which is measured through Nephelometric Turbidity Units (NTUs). The state has set this turbidity level at 5 ntu. One of the several spikes this year on Hangman Creek measured over 400 ntu. You should go and read the most recent report from the Spokane Riverkeeper (and all the incredible volunteers who helped measure and record this data). Data like this will help organizations, such as the Riverkeeper, to protect our river. If you would like to sign up as a citizen-scientist and help out with this amazing project, check out this informational page and contact Jule Schultz (jule@spokaneriverkeeper.org). Or stay informed by signing up for their mailing list.
Upcoming Events
There's a few fun upcoming events this spring to get you active and ready for the fishing season:
On Sunday March 24th, Spokane Women on the Fly (SWOTF) and Spokane Falls Trout Unlimited (SFTU) will have another fly tying event. It will be from 2:00 - 4:00pm over at Lumberbeard Brewing (25 E 3rd Ave, Spokane, WA 99202). No experience is necessary and fly tying tools and materials will be provided, but be sure to sign up here. Cost is just $8. The fly pattern Diane Ragan Smith will be teaching is an ant pattern which is a very useful fly to have for trout on streams, rivers, and lakes and is also a great pattern for panfish and smaller bass in ponds, lakes, and slack water zones on larger rivers in Eastern Washington.
There is also casting practice on Saturday April 13th over at the south end of Audubon Park starting at 11:00am. No experience or equipment necessary, and it's completely free! It's a great opportunity to learn how to fly cast or to practice/learn new skills like the double haul. I am planning on being at the casting practice to help out and to answer any questions about fly fishing the Spokane River and nearby lakes. Email spokanewomenonthefly@gmail.com if you need equipment or if you have any questions about the event.
Lastly, with the fishing season on the Spokane coming to a close until May 25th, the lakes near the city are almost thawed out enough for some spring stillwater trout fishing. We'll be hitting the lakes soon and we'll start having some fishing reports coming as well. If you would like to do a guided trip for some stillwater trout fly fishing email us at info@flyfishspokane.com or call Chad (425) 563-8211 or me at (214) 732-2283 to schedule.
425) 563-8211425) 563-8211
References:
Waters, T. F. 1995. Sediment in streams: sources, biological effects, and control. American Fisheries Society Monograph 7.
