Is 170 E over Cst S Brentwood Blvd
St. Louis County, Missouri · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Is 170 E over Cst S Brentwood Blvd in St. Louis County, Missouri, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1968 and reconstructed in 1986, making it 57 years old at the 2025 inventory.
- It carries about 41,851 vehicles a day (traffic count year 2024).
- Its listed owner is the state highway agency.
- It is one of 589 of the 906 inventoried bridges in St. Louis County rated fair (65.0%); 45 (5.0%) 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 → (38.64029, -90.34516)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 6 | Satisfactory condition |
| Superstructure | 7 | Good condition |
| Substructure | 6 | Satisfactory condition |
Bridge details
| Structure | Continuous steel stringer or multi-beam girder |
| Length | about 125 ft |
| Location | S 16 T 45 N R 6 E |
| NBI structure number | 2416 |
| Condition class | Fair |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Missouri department of transportation.
Busiest bridges in St. Louis County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Is 270 E over Sugar CR | 1962 | 212,715 | Fair |
| Is 270 E over Rp IS270E to IS64W Rp | 1993 | 199,283 | Fair |
| Is 270 E over Cst Conway Rd | 1964 | 182,944 | Poor |
| Is 270 E over Is 44 Rp IS270E to Is | 1962 | 176,520 | Fair |
| Is 64 E over Hampton CR | 1957 | 166,599 | Fair |
| Is 64 E over E Fk Deer CR | 1957 | 166,599 | Fair |
All bridges nearby: St. Louis County, MO bridge conditions · every bridge in St. Louis County · Missouri bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.