940.8 Raised Medians
Raised medians are the most effective access management strategy on high-volume urban routes. Roadways with raised medians are at least 25 percent safer than multi-lane undivided sections and 15 percent safer than two-way left-turn lane cross-sections in such high traffic situations.
In general, use of raised medians is recommended where current and projected traffic volume is greater than 28,000 average annual daily traffic (AADT). Raised medians are especially recommended in corridors where the traffic volume is high, the density of commercial driveways is high (over 20 -30 per mile in both directions), and other access management strategies such as driveway consolidation and corner clearance are not practical. Raised medians are to be used on arterial facilities with three or more through traffic lanes in each direction.
| Roadway Classification | In Current and Projected Urban Areas | In Rural Areas |
|---|---|---|
| Major, Freeway | Not applicable | Not applicable |
| Major, Non-Freeway | Raised median when current and projected traffic exceeds 28,000 AADT | flush median |
| Minor | Raised median when current and projected traffic exceeds 28,000 AADT | flush median |