Longjohn Slough Fishing in Cook County, Illinois

• Overview

  Longjohn Slough is set in Cook County, Illinois. The surface lies 702 feet up. Surface area is around 53 acres, which gives you real water without needing a boat. It is among the larger waters listed here for Cook County. For supplies, Willow Springs is 2.2 miles out. Naperville sits 15 miles out, and it is the nearest city worth the name. A county boundary sits nearby, which can matter for local access rules.

• Where to Fish on Longjohn Slough

  The records we hold are silent on depth, so plan to find it yourself. A soft bed grows weed late into autumn, which keeps fish shallow. Where the bottom changes texture, fish gather; find that line. Survey and observation records for Cook County include common carp, bluegill, green sunfish and gizzard shad. Records at this level tell you what is in the area. Fish Longjohn Slough to its features, not to its size.

• Seasonal Patterns

  Long-run averages give July about 74°F and January about 22°F. The season turns properly here, and fish follow it closely. Ice is part of the season here, ending near mid March. Break-up sits around mid March on average, with the water closing again about mid December. The weeks after the thaw and the ones before the freeze are the strongest. Longjohn Slough runs to that rhythm year in and year out.

• Tackle & Baits

  Public data does not answer the access question here. A car park sits roughly half a mile away. A picnic site half a mile off makes this workable with family in tow. Public toilets are recorded roughly half a mile off. For the carp, bait a margin spot and sit on it; corn and bread still work. Rules differ from one water to the next round here. Some ground is open by custom rather than by right, so tread carefully. Should this one be busy, Crawdad Slough is 0.3 miles off. For Longjohn Slough, the notice at the access point is the final word.