Twelve Mile Lake fishing: Walleye, Channel Catfish
Target species: Walleye, Channel Catfish
The reservoir
Twelve Mile Lake covers 639 acres in Iowa, across Union County. It is a reservoir: 92.7% of it is 32 feet deep or less; the deepest point measured is at least 40 feet (12.2 m). Our records hold 3 species for this water.
Stocking: 16,264,039 fish, 2012–2025
Iowa DNR records list 16,264,039 fish released into this water from 2012 to 2025.
- Walleye: 16,253,184 in 2012–2025
- Channel Catfish: 10,855 in 2013–2017
Depth and bottom
Deepest measured point: at least 40 ft (12.2 m). That is the deepest contour line: the bottom goes deeper. 92.7% of the water is 32 feet or shallower. We hold 87 depth contour lines for this water.
- 0–2 ft: 15% of the water
- 2–4 ft: 4.7% of the water
- 4–6 ft: 5.5% of the water
- 6–8 ft: 5.8% of the water
- 8–10 ft: 6% of the water
- 10–12 ft: 7.1% of the water
- 12–14 ft: 6.2% of the water
- 14–16 ft: 6.4% of the water
- 16–18 ft: 5% of the water
- 18–20 ft: 5.3% of the water
- 20–22 ft: 5.5% of the water
- 22–24 ft: 4.4% of the water
- 24–26 ft: 4.4% of the water
- 26–28 ft: 3.9% of the water
- 28–30 ft: 3.6% of the water
- 30–32 ft: 3.9% of the water
- 32–34 ft: 3.7% of the water
- 34–36 ft: 3.3% of the water
- 36–38 ft: 0.4% of the water
2 target fish, led by Walleye
- Walleye — Feeding water: 50–75°F.
- Channel Catfish — Feeding water: 70–85°F.
Also recorded here: Sauger.
Water and conditions
Our water temperature readings average 74°F; they do not cover the whole year, so this is not a yearly average. pH averages 8.2. These readings span 2017–2024.
Where this data comes from
- Iowa DNR — Iowa DNR: depth contours: class A, a survey of the bottom.
