Highwood Pass down to High River
The Highwood starts high, in Peter Lougheed Provincial Park below Mount Arethusa in the Highwood Pass, and runs south beside the Kananaskis Trail, Highway 40, between the Elbow-Sheep and Don Getty wildland parks. It swings east along Highway 541 through Longview, passes the town of High River, and ends in the Bow southeast of Calgary. Upstream it is Kananaskis Country cutthroat water; downstream it becomes a ranchland river that feeds the busiest trout float in the province.
It is also a river that floods. Wikipedia lists exceptional floods in 1894, 1899, 1902, 1908, 1912, 1923, 1929, 1932, 1942, 1995, 2005 and 2013, and three people died when the Highwood rose in June 2013. Respect any high streamflow advisory, because the gravel bars you walked last August may not be where you left them.
Two rulebooks and a 500-metre footnote
Alberta's 2026 ES1 table splits the river into three pieces, all under a bait ban. From the headwater at the Storm Creek and Mist Creek confluence down to the Kananaskis Country boundary, including tributaries except Storm Creek, the season runs June 16 to August 31 with a limit of 5 whitefish over 30 cm and 2 brook trout, every other trout catch and release, and then September 1 to October 31 with whitefish also at 0. From the K-Country boundary down to 500 metres above the mouth, including tributaries except the Sheep River, it is open June 16 to October 31 with 0 trout and 5 whitefish over 30 cm. The last 500 metres before the Bow follow Bow River rules: open all year, 0 of everything.
That means the Highwood is closed to fishing from November through June 15 almost everywhere except that short stretch at the mouth. June 16 is the regional opener, and Bow River Troutfitters describes crowds on well-known southern streams that week. Kananaskis also requires a Kananaskis Conservation Pass for vehicles that stop in the area; the shop quoted $15 a day or $90 a year when it was introduced.
The rainbows that come up from the Bow
Fish Tales Fly Shop's Bow River calendar explains why the lower Highwood matters to Calgary anglers even when they never fish it: the larger Bow rainbows move up the Highwood to spawn in spring, so there are fewer 19-inch-plus fish in the Bow from late April into May, and they drop back into the main river on the June high water. That spawning run is one reason the river below the K-Country boundary is catch and release.
The Highwood also decides what the lower Bow looks like. Fish Tales reports repeatedly note good clarity on the Bow above the Highwood and much worse visibility below it after rain, and Bow River Troutfitters advised floaters to stick to river left after the junction while the Highwood was still spitting dirt.
Bull trout, cutthroat and the upper valley logging fight
Bull trout and westslope cutthroat are both listed as Threatened under the federal Species at Risk Act, and Bow River Troutfitters notes that the 2020 bull trout recovery strategy maps nearly the whole Highwood as critical habitat. In 2023 Spray Lake Sawmills planned more than 1,100 hectares of clearcut logging beside Highway 40 in the upper valley and built an access road and bridge across the river. DNA testing commissioned by CPAWS found bull trout in creeks next to the planned cuts, DFO opened an investigation into the missing permits, and by February 2024 the company, by then West Fraser, had paused operations. The mayors of Okotoks and High River and more than 6,600 members of the public wrote to oppose it.
For anglers the practical point is simple: the upper Highwood is spawning water for both species. Land fish quickly, keep them in the net, and the same shop suggests a stream thermometer and stopping when the water hits 19 C.
Numbers from Diebel's Ranch
The ECCC gauge on this page is at Diebel's Ranch, west of Longview on the foothills reach, so it reads the mountain water before the lower tributaries join. ECCC's monthly means there are about 38 cubic metres per second in June, 17 in July, 7 in August, 5 in September and 4 in October; the station only reports from March to October. The 150 to 600 cfs range on this page is that July to October band, because no shop quotes a wading number for the Highwood. June water, at 1,300 cfs or more on average, is runoff. On September 24, 2026 the gauge read 4.23 m3/s, about 150 cfs, the low end of normal for fall.
Dry flies after June 16
Nobody publishes a hatch chart for the Highwood alone, so this table leans on nearby sources. Bow River Troutfitters recommends big, bushy Stimulators for eastern slope cutthroat, parachute ants in size 18 and small Chubbies when nothing else works, and green and brown drakes in sizes 10 to 14 in early summer. In September 2026 it reported cutthroat moving to large October caddis patterns. Fish Tales adds hoppers and backswimmers on the eastern slope streams into late September. For the stonefly and mayfly dates, Crowsnest Angler's chart from the next valley south is the closest published guide: golden stones through early July, PMDs mid-June through July, olives again from mid-August.