Mountainside Drive over Mill Brook
Morris County, New Jersey · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Mountainside Drive over Mill Brook in Morris County, New Jersey, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1929 and reconstructed in 1989, making it 96 years old at the 2025 inventory.
- It carries about 1,116 vehicles a day (traffic count year 2023).
- Its listed owner is the county highway agency.
- It is one of 383 of the 509 inventoried bridges in Morris County rated fair (75.2%); 27 (5.3%) 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 → (40.86753, -74.54478)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 6 | Satisfactory condition |
| Superstructure | 5 | Fair condition |
| Substructure | 6 | Satisfactory condition |
Bridge details
| Structure | Steel stringer or multi-beam girder |
| Length | about 26 ft |
| Location | 0.05 Mile N. Grist Mill |
| NBI structure number | 1400773 |
| Condition class | Fair |
Source: FHWA National Bridge Inventory, 2025 data as reported by the New Jersey department of transportation.
Busiest bridges in Morris County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I80 I280&RAMPS B&f over Troy Brook Branch | 1968 | 186,760 | Good |
| Rt I-287 over Eden Ln Rvr&morr&erie RR | 1970 | 161,936 | Fair |
| I-80 over Smith Road | 1973 | 161,136 | Fair |
| I-80 Eastbound over Stoney Brook Road | 1958 | 152,398 | Fair |
| I-80 WB over Stoney Brook Road | 1958 | 152,398 | Fair |
| I 287 NB and SB over Malapardis Brook | 1954 | 146,050 | Fair |
All bridges nearby: Morris County, NJ bridge conditions · every bridge in Morris County · New Jersey bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.