Mantua Reservoir
Toxic algae bloom at Mantua
- Keep dogs out of the water — blooms can be deadly for them
- Don’t swim, and steer clear of scum when wading or boating
- Don’t drink the water
- Keeping fish? Discard the guts and rinse fillets in clean water
- Boat RampWarning
- North ShoreWarning
- Northeast Boat RampWarning
Today’s report
Mantua Reservoir is under a Warning advisory today. The advisory is for a harmful algal bloom at 3 monitored sites and replaces the fishing rating until it’s lifted — keep dogs out of the water and check habs.utah.gov before you go. The DWR last stocked rainbow trout (10,000 fish) on September 29. This Afternoon's forecast: sunny, 63°F.
- Warning advisory posted (algal bloom) — it replaces the fishing rating until it’s lifted
- stocked 18 days ago
- calm, fishable weather
Current conditions
Stocking
Last stocked Sep 29, 2026 — rainbow trout (10,000 fish).
| Date | Species | Quantity | Avg length |
|---|---|---|---|
| Sep 29, 2026 | rainbow trout | 10,000 | 9.57" |
| Feb 9, 2026 | rainbow trout | 5,000 | 9.82" |
| Sep 30, 2025 | rainbow trout | 10,000 | 10.4" |
| Mar 18, 2025 | rainbow trout | 5,000 | 9.82" |
| Oct 28, 2024 | rainbow trout | 3,246 | 10.17" |
| Oct 22, 2024 | rainbow trout | 1,304 | 10.55" |
| Oct 18, 2024 | rainbow trout | 250 | 10.55" |
| Sep 16, 2024 | rainbow trout | 2,520 | 9.97" |
Best time to fish Mantua Reservoir
The DWR has stocked Mantua Reservoir 31 times over the last 6 seasons, and 74% of those plants landed in June, September, October — the freshest fish and the easiest bite usually follow within a week or two of a stocking.
Species
Location
Nearby waters (within ~25 mi):
Regulations
No water-specific rules listed for this water in the current Utah Fishing Guidebook — statewide general rules and daily limits apply (trout limit 4, combined). Verify in the current guidebook before you fish.