Knowles Hill Road over Brock Brook
Good Condition91 years old96 vehicles/day
Location
| State | New Hampshire |
| County | Grafton |
| Location | 3.8 Mi From Shin Valley |
| Carries | Knowles Hill Road |
| Crosses | Brock Brook |
| Coordinates | 43.63788, -71.85909 |
Condition Ratings
| Overall Condition | Good |
| Deck | 9 (Excellent) |
| Superstructure | 9 (Excellent) |
| Substructure | 9 (Excellent) |
| Channel/Waterway | 8 (Very Good) |
| Scour Critical | 8 — Stable, low risk |
Physical Characteristics
| Material | Wood or Timber |
| Design | Slab |
| Total Length | 36.1 ft (11 m) |
| Max Span | 32.2 ft (9.8 m) |
| Deck Width | 16.4 ft (5 m) |
| Deck Area | 55 sq m |
| Main Spans | 1 |
| Year Built | 1935 (reconstructed 2018) |
Traffic
| Avg Daily Traffic | 96 (2023) |
| Lanes On Bridge | 1 |
Inspection & Ownership
| Last Inspection | 823 |
| Inspection Frequency | Every 24 months |
| Owner | City/Municipal Highway Agency |
| Historical Significance | Bridge is possibly eligible (requires evaluation) |
| Structure Number | 000300940010800 |