Colorado River Granby to Kremmling Colorado: Finding Places to Fish Along Highway 40

Some stretches of river require maps, four-wheel drive, backpacks and a willingness to walk half a day before making the first cast.

Then there are rivers that seem to travel with you.

The Colorado River between Granby and Kremmling, Colorado, is one of those.

For much of this journey, U.S. Highway 40 and the railroad accompany the river across Middle Park, sometimes close enough that I can glance from the highway and begin mentally fishing a riffle before we've even found a place to pull over.

That's dangerous behavior for an old fisherman.

Paulette has learned to recognize the symptoms.

I slow down.

My head turns toward the river.

There's a little gravel road ahead.

Then comes the inevitable:

"I wonder if we can get down there?"

That question has probably added a few thousand miles to our travels over the years.

But that's part of exploring a river.

Our Colorado River journey began among snowfields in Rocky Mountain National Park. We followed that young mountain stream through the Kawuneeche Valley to Grand Lake, then south through Shadow Mountain Lake and Lake Granby.

Now we leave the big headwater reservoirs behind.

The Colorado River becomes a river again.

It flows west from below Granby Dam, passes Windy Gap, works through ranch country and Hot Sulphur Springs, squeezes through Byers Canyon, passes Parshall, receives tributaries draining Middle Park, and eventually approaches Kremmling.

And somewhere along Highway 40, there is probably a trout waiting behind a rock.

Let's go find him.

Leaving Granby and Finding the Colorado River Again

Granby sits at an important crossroads in the upper Colorado River country.

Behind us are Grand Lake, Shadow Mountain Reservoir and Lake Granby.

Ahead of us is Middle Park.

The transition is noticeable.

The towering enclosed feeling of Rocky Mountain National Park begins giving way to broader valleys, ranchlands, sagebrush, cottonwoods and open views.

The Colorado River emerging below Lake Granby is no longer merely the little headwater stream we followed through the Kawuneeche Valley.

Its character has changed.

Its flow is now influenced by reservoirs, diversions, tributaries and water-management operations.

But it remains cold trout water.

And Highway 40 begins settling into the river corridor.

This is one of those drives where I don't recommend being in a hurry.

Granby to Kremmling is only about thirty miles by highway.

A fisherman can turn thirty miles into an all-day expedition without even trying.

Highway 40, the Railroad and the Colorado River

I enjoy roads that follow rivers.

They usually exist for the same reason the river exists.

The terrain told them where to go.

Railroads understood that lesson long before interstate highways.

Mountain grades are expensive, and river valleys provide natural corridors through difficult country.

So between Granby and Kremmling, the Colorado River, Highway 40 and the railroad repeatedly share the same broad route through Middle Park.

Sometimes the railroad hugs the river while Highway 40 sits farther away.

Sometimes all three nearly come together.

Then the river bends away again.

For an angler, that creates opportunity but also responsibility.

Seeing water from the highway does not automatically mean you can fish it.

Much of Colorado contains a patchwork of private ranches, public land, state wildlife areas and federal access.

I never assume.

I look for established public access, CPW signs, BLM signs and designated parking areas.

That keeps the fishing enjoyable and keeps us on the right side of the fence, literally and figuratively.

Middle Park Geography

This broad mountain basin is known as Middle Park.

It lies between major mountain ranges and is drained largely by the upper Colorado River and its tributaries.

The Continental Divide rises to the east.

The Gore Range forms a dramatic wall farther south and west.

To the north lie additional mountain uplands and the approaches toward North Park.

The valley floor is comparatively open.

Sagebrush country mixes with irrigated ranch meadows. Cottonwoods and willows mark waterways. Mountains form the horizon.

I grew up around cattle country in the Kansas Flint Hills, and perhaps that is why landscapes like Middle Park feel familiar even when the mountains clearly announce that Kansas is a long way behind us.

Ranches follow water.

Wildlife follows water.

People follow water.

And Highway 40 follows the Colorado.

Ancient People Along the Upper Colorado

That relationship between people and water began thousands of years before Highway 40.

Native people traveled through Middle Park long before Europeans arrived.

The Ute people became especially associated with Colorado's mountain country, moving seasonally through valleys and high passes to hunt, gather plants, fish and trade.

Earlier peoples had occupied and traveled through the central Rocky Mountains for thousands of years.

A valley like this offered things humans have always needed:

water, game, edible plants, travel corridors and relatively protected country between high mountain ranges.

The river was not scenery.

It was survival.

Whenever I stand beside an old Western river, I try to remember that.

We arrive with graphite fly rods, Gore-Tex waders and GPS.

People were successfully living in this country long before any of those things existed.

Readers interested in that much older chapter of Colorado history can continue with The Original Coloradans.

Windy Gap Watchable Wildlife Area

Only a few miles west of Granby, Highway 40 brings us to Windy Gap Reservoir and the Windy Gap Watchable Wildlife Area.

This is where I put the fishing rod down.

Not because there aren't fish in the neighborhood.

Because fishing is prohibited within the Watchable Wildlife Area.

Colorado Parks & Wildlife manages the approximately 12-acre site specifically for wildlife viewing. It is open from sunrise to sunset and includes an interpretive trail and restroom facilities.

Hunting and fishing are prohibited.

And that's perfectly fine with me.

I have a camera too.

Windy Gap has become one of Colorado's notable wildlife-viewing locations. More than 150 species of birds and wildlife have been recorded around the reservoir area, including waterfowl, raptors and occasional river otters.

This is a good place to stop, stretch your legs and scan the water.

Bring binoculars.

Bring the telephoto lens.

Leave the fly rod in the truck.

Windy Gap and the Working Colorado River

Windy Gap also tells another story.

This is not an untouched river.

Windy Gap Reservoir was created as part of a water-diversion project serving Colorado's Front Range.

The shallow reservoir has affected the river's ecology, including water temperature, sediment movement and fish passage.

Grand County and water-management organizations are involved in the Colorado River Headwaters Project, which includes efforts to improve river connectivity and aquatic habitat around Windy Gap.

That is important for trout.

A healthy trout stream isn't simply water containing trout.

It needs appropriate temperature, dissolved oxygen, gravel, insects, cover, connected habitat and natural river processes.

When one part changes, the others notice.

So do the fish.

Current Colorado River Water Levels

One advantage we have today is immediate river information.

The USGS maintains a gauge on the Colorado River at Windy Gap near Granby.

On the morning of August 24, 2026, that gauge was reporting an instantaneous flow of about 193 cubic feet per second.

For perspective, the long-term median daily discharge for August 24 at that gauge is about 142 cfs, based on 44 water years of record.

That tells us today's river is running above the historical median for the date.

But don't memorize 193.

By the time you're standing there with a fly rod, it may be entirely different.

Check current USGS flows before fishing.

Also check water temperature.

Flows can change with precipitation, reservoir operations, diversions and seasonal runoff.

The Colorado is alive.

Treat any printed flow figure as a snapshot, not a promise.

Finding Places to Fish Along Highway 40

Now we come to the enjoyable part.

The stretch from Granby toward Kremmling contains some outstanding trout water, but access varies.

The key is looking for legitimate public fishing access rather than simply convenient-looking water.

BLM maintains several access areas along the broader Granby-to-Kremmling corridor, while Colorado Parks & Wildlife manages the substantial Hot Sulphur Springs State Wildlife Area.

A portion of this upper Colorado corridor has been recognized as Gold Medal trout water.

That's enough to make any trout fisherman sit a little straighter in his seat.

Hot Sulphur Springs Colorado

Continuing west on Highway 40 brings us to Hot Sulphur Springs.

This small Grand County community sits directly in the Colorado River valley and serves as the county seat.

The town gets its name honestly.

Natural hot springs have attracted people here for generations.

For Native people, mineral springs and river valleys were known long before modern settlement.

European-American development eventually turned the springs into a destination, and today's community retains the character of an old Colorado mountain town.

For an angler following the Colorado, however, Hot Sulphur Springs means something else.

Access.

Hot Sulphur Springs State Wildlife Area

The Hot Sulphur Springs State Wildlife Area is one of the most useful public-access resources on this stretch of river.

Colorado Parks & Wildlife lists the SWA at approximately 2,160 acres, with coldwater-stream fishing, hiking, wildlife viewing and photography among the available activities.

It isn't one continuous block.

The SWA includes multiple units.

These include the Hot Sulphur Springs State Ranch, Lone Buck Unit, Jenny Williams Unit, Joe Gerrans Unit and the Paul F. Gilbert Fishing Area, among others.

Several are reached from Highway 40 west of Hot Sulphur Springs.

This is exactly what I'm looking for on a river-driving trip.

Legal parking.

Clearly identified access.

And trout water.

For most Colorado State Wildlife Areas, visitors age sixteen and older need a valid Colorado hunting or fishing license or SWA pass. Always check the current CPW rules before visiting because access regulations can change.

Byers Canyon

Immediately west of Hot Sulphur Springs, the geography tightens.

The Colorado River enters Byers Canyon.

Highway 40 and the railroad squeeze through with it.

This is one of my favorite transitions along the drive because the broad valley suddenly narrows and reminds you that rivers choose the easiest path through mountains, not necessarily an easy path.

Rock walls rise beside the road.

The railroad runs near the river.

The Colorado becomes more confined.

Deep runs, riffles, pockets and current seams begin looking extremely interesting.

The scenery is beautiful.

But access requires care.

Steep terrain, highway traffic, railroad property and private land all demand attention.

I never park where I'm creating a hazard and never cross railroad property casually.

A trout is not worth becoming a hood ornament.

The Gold Medal Water Below Byers Canyon

This is where the fishing becomes especially interesting.

Current Colorado regulations divide this reach into different management sections.

From Lake Granby Dam downstream to the U.S. 40 bridge roughly three miles west of Hot Sulphur Springs, the trout bag and possession limit is two fish.

From that bridge downstream to the confluence with Troublesome Creek, approximately five miles east of Kremmling, regulations become much more conservation-oriented:

Artificial flies and lures only.

All trout must be returned immediately to the water.

That's my kind of trout water.

It also fits perfectly with the fish-handling practices I have come to value more with every passing year.

Troublesome Creek

Troublesome Creek joins the Colorado east of Kremmling and forms an important regulatory landmark.

It is also one of several tributaries adding water and habitat complexity to the upper Colorado system.

Tributaries are nurseries, temperature refuges, sources of nutrients and travel corridors.

They may look insignificant compared with the main river.

Ecologically, they are anything but.

Williams Fork River

Another important tributary in this region is the Williams Fork River, entering the Colorado near Parshall.

The Williams Fork drains mountain country to the south and is regulated by Williams Fork Reservoir upstream.

Its contribution influences Colorado River flow and temperature downstream.

For anglers, tributary mouths deserve attention.

Different currents meet.

Food concentrates.

Temperature may change.

And trout understand those advantages considerably better than fishermen do.

Parshall Colorado

Between Hot Sulphur Springs and Kremmling lies the little community of Parshall.

This is ranch country.

The Williams Fork enters the Colorado nearby, and the surrounding river corridor provides additional opportunities to explore.

Parshall doesn't need neon signs advertising itself as fishing country.

The river does that.

I enjoy places like this.

Small community.

Railroad.

Ranches.

Mountains.

And a trout river slipping past.

Approaching Kremmling

As we continue west, the country begins opening again.

Kremmling sits at an important hydrologic crossroads.

Here several river systems come together.

And one of the most important is the Blue River.

The Blue River

The Blue begins high in Summit County near the Continental Divide.

It flows north through Breckenridge and Dillon Reservoir, then continues through mountain country toward Kremmling.

Near Kremmling, the Blue joins the Colorado River.

That confluence changes the Colorado.

More water.

More habitat.

More river.

BLM manages a Confluence Recreation Area that provides access to the lower Blue River and the confluence with the Colorado, including opportunities for wade fishing and boating access.

Standing near a river confluence always makes me think about maps.

We draw separate blue lines and give them separate names.

The water doesn't care.

The Blue arrives.

The Colorado accepts it.

From that point downstream, they're one river.

Kremmling Colorado

Kremmling has long been shaped by ranching, transportation and the surrounding rivers.

It sits near the junction of Highway 40 and Highway 9, making it a natural base for exploring the upper Colorado and Blue River country.

For anglers, Kremmling is particularly useful because BLM's Kremmling Field Office manages numerous river access sites downstream and around the community.

The river ahead will eventually take us into much wilder country.

Gore Canyon waits downstream.

So does Pumphouse.

Radium.

State Bridge.

But that's another chapter.

For now, we've got trout to catch.

Trout Species Between Granby and Kremmling

The primary gamefish in this reach are:

Brown Trout

Brown trout are beautifully suited to the Colorado.

They favor structure.

Undercut banks.

Deep runs.

Boulders.

Current breaks.

They can become wonderfully selective and maddeningly intelligent.

Large browns often become more predatory as they mature, making streamers particularly interesting.

Rainbow Trout

Rainbows provide the other major trout component of this fishery.

They often occupy riffles, runs and feeding lanes where current delivers aquatic insects.

Both species respond well to fly and spinning presentations when conditions are right.

Spinning Rods and Reels

For this portion of the Colorado River, I like a 6½- to 7-foot light or medium-light spinning rod.

Pair it with a 1000- to 2500-size spinning reel.

The drag matters.

A good Colorado River trout can use current remarkably well, and a smooth drag protects light line.

Spinning Line

I would carry:

• 4- to 6-pound monofilament

• 4- to 6-pound fluorocarbon

• Light braid with a fluorocarbon leader

Clear water favors subtle presentations.

Remember that special-regulation sections may require artificial lures only.

Always know which section you're standing in before opening the tackle box.

Spinning Lures

My small-lure box would include:

• Inline spinners

• Small spoons

• Marabou jigs

• Tiny minnow plugs

• Small jerkbaits

Colors?

I like natural tones first.

Silver.

Gold.

Brown trout patterns.

Olive.

Black.

In cloudy or stained water I may experiment with brighter finishes.

The fish get the final vote.

Spinning Baits

Where bait is legal, anglers may use traditional trout baits permitted under current Colorado regulations.

But bait is prohibited in the artificial-flies-and-lures-only section below the U.S. 40 bridge west of Hot Sulphur Springs to Troublesome Creek.

That distinction matters.

Check the current CPW regulation before fishing.

"I didn't know" has never been a particularly impressive fishing technique.

Fly Rods and Reels

For most of this river I would carry a 9-foot 5-weight fly rod.

It is the old pickup truck of trout rods.

It does nearly everything reasonably well.

A 4-weight can be delightful during lower flows and dry-fly fishing.

A 6-weight becomes useful for larger streamers, windy conditions and heavier rigs.

Match the rod with a quality reel and smooth drag.

Fly Line

A weight-forward floating line handles most fishing here.

I generally carry leaders from roughly 9 to 12 feet depending upon conditions.

Useful tippet sizes include:

3X to 5X for much of the fishing.

6X when fish become particularly selective.

Heavier tippet for streamer fishing.

Dry Flies

I want a Colorado fly box containing:

• Parachute Adams

• Blue-Winged Olives

• Pale Morning Duns

• Elk Hair Caddis

• Griffith's Gnats

• Stimulators

• Ants

• Beetles

• Grasshopper patterns

Terrestrial fishing can become especially enjoyable later in summer.

A grasshopper making an unfortunate landing near a cut bank can become a very fortunate event for a fisherman.

Nymphs

Nymph fishing catches trout because trout spend much of their lives eating below the surface.

I would carry:

• Pheasant Tail

• Hare's Ear

• Prince Nymph

• Copper John

• Zebra Midge

• RS2

• Stonefly nymphs

• Caddis larvae

• Midge patterns

Watch insect activity and adjust size accordingly.

Sometimes changing from a size 16 to an 18 accomplishes more than changing the entire pattern.

Streamers

For brown trout, I wouldn't travel this river without streamers.

Try:

• Woolly Buggers

• Sculpin patterns

• Leech patterns

• Small articulated streamers

• Minnow imitations

Work them along undercut banks, deep pools, boulders and shaded structure.

Early morning and cloudy weather can be particularly interesting.

Productive Trout Water Temperatures

Trout fishing isn't simply about catching fish.

It is about releasing healthy fish when release is required or intended.

Water temperature matters enormously.

I generally consider the upper 40s through upper 50s and low 60s Fahrenheit productive trout water.

As temperatures rise into the mid-60s, I begin paying close attention.

When water approaches 68°F, I seriously consider putting the trout rod away.

Warm water carries less dissolved oxygen.

A trout hooked and fought in warm water may appear to swim away successfully and still die later from physiological stress.

No trout is worth that.

Carry a thermometer.

Use it.

Best Time of Day to Fish

In summer, I like early morning.

Water is coolest.

Light is gentle.

Insect activity may be good.

Trout haven't spent the day watching fishermen parade every fly ever tied past their noses.

Evening can also be excellent.

During spring and fall, midday may become productive as temperatures warm.

Cloudy weather can extend feeding activity.

The river determines the schedule.

I merely try to listen.

Barbless Hooks

On catch-and-release water, I strongly favor barbless hooks.

If the fly or lure has a barb, pinch it down.

A barbless hook usually comes free quickly.

Less handling.

Less tissue damage.

Less time out of water.

And yes, occasionally the trout comes free before I wanted him to.

I can live with that.

Wet Hands

Before touching a trout, wet your hands.

Trout carry a protective slime coating.

Dry hands can damage it.

I don't squeeze a fish.

I support it gently.

Better yet, I leave it in the water.

Keep the Trout Fully Submerged

On mandatory catch-and-release sections, my goal is to keep the trout fully submerged while removing the hook.

If I want a photograph, I prepare the camera first.

Then lift the trout briefly.

Click.

Back into the water.

Not ten photographs.

Not twenty.

One good photograph is enough.

The trout has other appointments.

Rubber Nets

I strongly recommend rubber landing nets.

Rubber mesh is much gentler on fish than old-fashioned abrasive or knotted netting and tangles fewer hooks.

Once the trout is in the rubber net, I can keep the fish fully submerged while removing the hook.

That is good for the fish.

And considerably easier on an old fisherman's nerves.

Reviving a Trout

If the fish needs recovery, support it gently facing into clean current.

Keep it upright.

Keep it submerged.

Don't drag it violently backward through the water.

Allow water to pass naturally across the gills.

Eventually you'll feel strength return.

The tail begins working.

The fish balances itself.

Then I loosen my hands.

When that trout decides he's ready, he leaves.

That's one of my favorite parts of fishing.

Boating and Floating

The Granby-to-Kremmling reach isn't merely wade-fishing country.

Sections can be floated under appropriate flows and conditions.

But river boating demands preparation.

Flows change.

Low water exposes rocks.

High water increases current speed and hazard.

Private-property boundaries complicate stopping along shore.

Byers Canyon requires particular knowledge and caution.

Anyone unfamiliar with the river should research the exact section carefully and consider using an experienced local outfitter.

A fishing raft is a wonderful tool.

It is not a substitute for judgment.

Public Fishing Access Near Kremmling

BLM provides several designated access points as we approach Kremmling.

Sunset Bridge Fishing Access

BLM's Sunset Bridge Fishing Access provides parking and a trail to approximately a quarter-mile of river access.

The bridge itself is private.

That's an excellent example of why anglers need to read signs rather than assume.

Barger Gulch Fishing Access

Barger Gulch provides another formal BLM fishing access, reached from Highway 40 through county roads.

Highway 9 / Kimball Bridge Access

Near Kremmling, the Highway 9 fishing access provides roughly half a mile of river access approximately one mile south of town.

These designated areas turn "I wonder if we can fish there?" into "Yes, we can."

That's always preferable.

Camping

Camping opportunities are plentiful in the broader Middle Park region, but not every fishing-access site permits camping.

For example, BLM identifies no camping at Sunset Bridge, Barger Gulch and the Highway 9 access.

That is why I never assume a parking area is a campsite.

Developed campgrounds and designated public-land camping can be found throughout the surrounding national forest, BLM and recreation areas.

Check current fire restrictions.

Colorado mountain summers can become extremely dry.

A campfire that seemed harmless at breakfast can become somebody's nightmare by afternoon.

Wildlife Along the River

This is still excellent wildlife country.

Watch for:

• Moose

• Rocky Mountain elk

• Mule deer

• Pronghorn in open country

• Black bears

• Coyotes

• Red foxes

• Beaver

• River otters

• Bobcats

• Mountain lions

• Bald eagles

• Golden eagles

• Ospreys

• Hawks

• Waterfowl

The riparian corridor acts like a wildlife highway.

Cottonwoods provide perches.

Willows provide browse and cover.

The river provides drinking water, fish and aquatic habitat.

After our earlier search for moose around Grand Lake and Granby, I don't stop looking simply because we've driven west.

A moose doesn't recognize the chapter break in my website.

Weather Through the Seasons

Spring

Spring means runoff.

Mountain snow begins melting.

The Colorado rises.

Water becomes cold, powerful and often discolored.

Fishing can be difficult during peak runoff, and wading may become unsafe.

Summer

Summer brings comfortable mornings, warm afternoons and thunderstorms.

Get on the river early.

Watch water temperature.

Watch the sky.

Lightning in open river country is persuasive.

Fall

Fall may be the finest season of all.

Cool mornings.

Stable water.

Active trout.

Changing cottonwoods and aspens.

Elk bugling in surrounding country.

Brown trout preparing to spawn.

The river feels different.

Quieter.

Older somehow.

Winter

Winter brings snow, ice and bitter mornings.

Fishing remains possible where open water exists, but safety becomes paramount.

Ice along riverbanks can make a simple step surprisingly dangerous.

Fish slowly.

Dress properly.

And remember that daylight disappears early behind mountains.

Getting There

From Granby, take U.S. Highway 40 west.

It really is that simple.

Windy Gap lies only a few miles outside town.

Continue west toward Hot Sulphur Springs.

Highway 40 follows the Colorado River corridor through Middle Park, then squeezes through Byers Canyon.

Beyond Hot Sulphur Springs you'll pass Parshall and continue toward Kremmling.

From Denver, the common route is Interstate 70 west to U.S. Highway 40, then over Berthoud Pass through Winter Park and Fraser to Granby.

From Grand Lake, take U.S. 34 south to Granby, then turn west on Highway 40.

From Silverthorne, Highway 9 follows the Blue River north toward Kremmling.

That route brings you directly into the country where the Blue and Colorado meet.

An Old Fisherman Along Highway 40

Some fishing trips are built around destinations.

This one is built around curiosity.

Paulette and I leave Granby.

The railroad appears beside us.

Then the Colorado River.

I see a riffle.

Then a bend.

Then a deep run beside a cottonwood.

I start wondering.

Is there public access?

Where can we park?

What's the water temperature?

What insects are coming off?

Is that an eagle sitting in the cottonwood?

Maybe we'll stop.

Maybe we'll fish.

Maybe I'll make three casts and spend the next hour photographing a moose.

That's the pleasure of following a river rather than simply arriving at one.

The Colorado River between Granby and Kremmling still feels connected to the ranching West I recognize from my boyhood.

The country is larger here than the little headwater valley.

The river is larger too.

We have reservoirs behind us.

Tributaries are joining.

The Blue River waits ahead.

And the Colorado is beginning to gather the strength that will eventually carry it through canyon country and into the desert Southwest.

If you'd like to see just how dramatic that transformation eventually becomes, take a look ahead at Colorado River fishing at Davis Dam and Lake Mohave, explore Colorado River recreation at Davis Camp, or walk with me along the Colorado River Heritage Trail at Lake Mohave.

But I wouldn't hurry there just yet.

We're still on Highway 40.

There's another public access sign ahead.

The fly rod is in the truck.

And somewhere behind the next bend, the Colorado River is waiting.