No Red Line Creek-specific exception appears in the checked Region 4 extraction, so the regional defaults apply: streams closed Apr 1 to Jun 14, trout and char catch-and-release from Nov 1 to Mar 31, and a single barbless hook requirement on all streams. Confirm the current synopsis and any in-season notices before fishing.

The creek's mouth sits at 50.50292, -116.42930, within the Horsethief Creek drainage in the Radium-Invermere-Fairmont corridor. No stream-order, channel-geometry or discharge figures were confirmed for Red Line Creek specifically in the local extraction, and no dedicated survey or beat data was found. That leaves size, gradient and flow character unconfirmed, unlike the better-documented water on Horsethief Creek itself.

With no direct fish records in the local extract, there is nothing confirmed to plan a trip around. If a legal, fishable reach with coldwater fish turns up, small-stream attractors and naturals are the sensible starting point: an Adams, Elk Hair Caddis or Stimulator up top, a Hare's Ear or Prince Nymph underneath, and small terrestrials through summer. Mayflies, caddisflies and stoneflies are the likely food base if coldwater fish are present, the same insect community that drives the fishing on Horsethief Creek and its better-documented siblings.

No named trailhead, road access point or parking area has been confirmed for Red Line Creek. It sits within the same Columbia Valley forest road network that serves Horsethief Creek and its other tributaries near Invermere, but no source ties a specific route or put-in to this creek.