When it Rains... Understanding Water Conditions by Cameron Black

When it Rains... Understanding Water Conditions by Cameron Black

We’ve all been there before. Lying in bed the night before a salmon or steelhead trip to your favorite small river.

You’ve been waiting all week for an opportunity to go and tomorrow’s your day. The reports are great and conditions are prime. You’ve spent all day and evening prepping, your gear is dialed, your waders are set out and the coffee maker is set to come alive at a wicked early hour. You’re in bed but can barely sleep, afraid that you may sleep past your alarm clock and second-guessing your plan for the next morning’s adventure.

cameron black layden black steelhead fishing kids fish

The author, fishing steelhead with his son.

You're just about dozing off, but then you hear it… it starts as a small purr but then turns into a roar. A roar that sounds like someone’s dropping five-gallon buckets of marbles down your roof.

Now you really can’t sleep.

The river’s going to blow out and you can feel it. It was only supposed to rain just a little, enough to keep the stream at the perfect level and open a highway for all the salmon and steelhead you can handle to rush up it. Is it going to be mud? Will it be too high? Will I be able to wade to that perfect little spot with the best drift around for miles? Should I not even make the drive and just hit the snooze button and get some much-needed sleep? The struggle is real...

Know what you’re dealing with…

fishing in the rain landing net
Playing the conditions is one of the toughest concepts for a beginning steelhead or salmon angler to master. Hit the river at the right time and fishing will be easy as the water clarity and level will put everything in your favor. The right amount of color and speed will move fish to all the sweet spots that you know and give the fish the right amount of cover to sit where they are the most comfortable. Not to mention keep them moving and coming by all day long. Hit the river too low and the fish will want to hide in the cover of riffles and rapids, hide in the darkest holes, or just sit low in the river and not want to move. Too high and the small stream will turn into a roaring torrent where fish skirt the sides with very little visibility to even take a shot at your offering.

Experienced anglers will have a multi-faceted understanding of the rivers they fish.

Everything from knowing where the water comes from, to how it responds when it’s a cold or warm front, where to fish it when it’s high and low, and how to use the forecast and gauges to know when to be there. Being able to use some prior homework and the tools available online, can create a combination that adds confidence to an angler’s plans that can be one of the most valuable assets to catching salmon and steelhead. 

cameron black steelhead fishing wilson

When that rain starts falling, this is where your homework comes in.

Before the rains hit, before the fish even show, you need to have a clear picture of what you’re dealing with when it comes to the river you want to fish.

Is it full of woody debris?
Is it a shallow gravel wash with a little cover?
Is it a river filled with huge boulder gardens?

Having that scouted out prior to the season will save you the guess work when the conditions go awry. Showing up to a large boulder field that is completely buried underwater with no signs on the surface where fish could be hiding can be a challenge if you haven’t laid eyes on it before. Attempting to decipher how deep a trench is on the far side of the river can be impossible unless you know the depth when it’s low. These spots can provide great refuge for the fish from currents and can hold fish that won’t be visible to the angler. Knowing where to cast, the depth, and if there are any snags will help immensely with digging out salmon or steelhead. Take any opportunity to scout your rivers preseason before the rains hit and the flows hide features that you’re going to want to know about later.

Bring out the Apps

Talking with guides from the previous generation about how they would have to drive to the rivers in the dark after the rain just to see if it’ll fish and then hurry to a phone to call and cancel or confirm the date seems like something out of the stone age. Today we have the ability to take a lot of guesswork out of what soaked up countless hours of missed sleep for the previous generation. The internet is your most useful tool when it comes to the rain and weather, but applying the data and forecasts correctly to your fishing will save countless wasted trips.

The first thing you need to do is find all the available collected data on your river or stream. My best advice is to search your river’s name and then the letters CFS or gauge. There are lots of federal agencies that have stream monitoring but occasionally you’ll need to access a State Department of Ecology or city municipality’s website for the data you want. Searching the CFS or “cubic feet per second” is a pretty standard term for monitoring stations that will report online. 

On top of that, there are many apps that compile the data in one easy to access step, but I urge a little caution as some apps only pull data from the host site every so often. Finding if a river is spiking in real-time can be difficult without the constant refreshing of data and some apps just don’t do that.

A helpful data point that can be shown on some of the graphs and tables would be the median daily statistic or the average height for that date year over year. This is generally shown on USGS monitoring stations and can be seen by little triangles on the graphs representing the CFS. Generally speaking, those triangles can give the angler some insight to where the river runs during “normal” flow. If I had to go to a new stream completely blind and pick a river height to fish, I’d start with those heights represented by the triangles.

river levels cfs fishing

Now, of course, there will be exceptions to that rule as much larger rivers sometimes fish better on the low side and the complete opposite for really small streams, the triangles will still help decipher if the river is running above or below average.

Where’s your water coming from?

Depending on whether you are fishing a dam-controlled river, a small coastal stream, or a large river pouring off the side of a mountain range, different weather patterns can have drastically different effects on the flows. Warm and cold fronts with varying snow level heights can cause rivers to swell or not even change at all, even if it seemed like it rained inches where you are. There have been countless times in my career where we’ve seen massive rains just below the snow line and were able to squeak out a few more days of fishing before the low snow melted and poured into the river

During a cold front with a lower snow level, most of the water will lock up and stay on the hillsides versus blowing out the river.

Knowing if the headwaters of the river you intend to fish are seated on a higher range or a coastal hillside can determine if you’ll even have an option of fishing the next day. In the graph below I took two rivers, one seated on a coastal range (red), and the other seated high in the mountain ranges, (green). At the start of the week, there was a cold front that dropped a ton of rain in the region and represented in the graph, the rain that fell at the coast stream entered the river immediately whereas the higher mountain range river held the water as snow and kept the river gradually falling.

Later in the week we had a warm front that caused the melting of the locked snow and the coastal range stream crested sooner and the high mountain range continued to rise past the coastal stream.

steelhead fishing cameron black chrome

Another variable you can decipher from the water graphs is when a river will clear after a rise. This takes a little more time on the river to determine, but knowing if a river clears extremely fast or slow will tell you when to be there after a crest. Keep track as these times of the season can be the most productive.

No data? No problem.

There are many fishy rivers around the country that don’t have a monitoring station on them by any agency. In fact, one of my favorite rivers doesn’t have any monitoring on it at all. The best way I approach this is to use monitoring stations from neighboring rivers that are coming from the same general area or mountain range. From going to the river repeatedly and keeping track of what the neighboring rivers are doing at the time, I have a pretty good idea of what the river is doing even without the local gauge. Keeping a river level journal can be helpful especially if you travel and fish a lot of rivers as too not confuse the numbers between them.

Utilizing all the tools at your disposal will help the learning curve when playing the river level games. Knowing what level and conditions you’re going to encounter before arriving can determine everything from the gear you’re going to pack, the type of rods you’ll use and even what techniques to deploy. Being efficient with your time and staying on the water that offers better opportunities will put more fish on the bank during the season versus a lot of wasted windshield time.


Cameron Black

Gone Catchin' Guide Service
Addicted Fishing


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1 comment

I thought I was the only one who suffered from fish insomnia. Thanks for sharing, Cameron!

Kevin Bushnell

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