M 99 over Prior Lake
Scott County, Minnesota · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- M 99 over Prior Lake in Scott County, Minnesota, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1986, making it 39 years old at the 2025 inventory.
- It carries about 400 vehicles a day (traffic count year 1995).
- Its listed owner is a city or municipal highway agency.
- It is one of 45 of the 129 inventoried bridges in Scott County rated fair (34.9%); 1 (0.8%) are rated poor.
- A fair rating means the lowest-rated major component scores 5 or 6 on FHWA's 0-9 scale: some deterioration or minor section loss, but the structure is sound. It is the middle class, not a warning.
View this bridge on a map → (44.72939, -93.4321)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 7 | Good condition |
| Superstructure | 7 | Good condition |
| Substructure | 5 | Fair condition |
Bridge details
| Structure | Timber slab |
| Length | about 71 ft |
| Location | W of Martinson Island |
| NBI structure number | 70513 |
| Condition class | Fair |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Minnesota department of transportation.
Busiest bridges in Scott County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 169 over Deans Lake Outlet | 1994 | 66,622 | Good |
| Mn 13 over Credit River | 1939 | 54,000 | Fair |
| Mn 101 over Th 13 | 2012 | 54,000 | Fair |
| Mn 13 over Dakota Ave | 2023 | 54,000 | Good |
| US 169 over Stream | 1994 | 47,006 | Good |
| US 169 over Stream | 1995 | 40,000 | Fair |
All bridges nearby: Scott County, MN bridge conditions · every bridge in Scott County · Minnesota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.