- Delaware uses SR-## for all state routes (e.g. SR-58)
- If the primary name is a street name and the road also has a US or state route (SR), add it to the alt name (e.g. Primary Name: Capitol Trl, Alternate Name1: SR-2, Alternate Name2: Kirkwood Hwy). If a divided road, also add the cardinal direction to the alt name. e.g. "SR-7 N" on the northbound side and "SR-7 S" on the southbound side. When using alt names, be sure to be consistent and avoid gaps in naming, as this can cause routing issues with detour prevention. If the road switches back and forth between divided and two-way you should add a simple SR-## Alt Name for the entire length as well to avoid detour prevention.
- Generally, regarding state route numbers, even numbers run east-west and odd numbers run north-south
- Some Delaware routes are continuations from other neighboring state routes. e.g., SR-273, SR-896, SR-299.
Locking standard
In Delaware we have a set minimum standard for locking roads based on segment type. Any road of a certain segment type must be locked at least to the rank (level) in the chart below. Roads may be locked higher for protection and special situations (areas with construction, tricky design, frequent mistakes, imaging inaccuracies, and the like), but should not be locked lower.
A great time to implement these locks is while bringing the road types of an area into compliance with the current US road type standards (FC and highway systems). Lock the roads based on type after they've been set to current US road type standards.
| Segment Type | Statewide |
|---|---|
| Freeway | 5 |
| Ramp | Highest rank of connected segments |
| Major Highway | 3 |
| Minor Highway | 3 |
| Primary Street | 1 (Auto) |
| Street | 1 (Auto) |
| Private Road | 1 (Auto) |
| • • • • Ferry • • • • | 5 |
| |-|-|-|-|-|-|-|-|-| Railroad |-|-|-|-|-|-|-|-|-| | 2 |
Note: Do Not Mass Edit just to update locks to these standards, these can be adjusted as you find them while editing other aspects of the segments such as FC, speed limits, naming, etc.
Some segments still warrant higher locks and care should be taken when setting segment lock to these standards to look for and protect these special setups with higher locks. Some examples; segments which are part of BDP, U-turn prevention, or using micro-doglegs, or other complex intersection setups.
Speed Limits
Delaware follows the national guideline for speed limits, with a few exceptions listed below.
Delaware guidelines
- When a speed limit changes at an intersection, the sign for the new speed zone can be found up to 200 feet after the intersection. Map the change at the junction if signs immediately after the junction on each side are different speed limits.
- If the speed limit changes more than 200 feet from the intersection, add a junction at the sign and make the speed limit change there.
- If opposing speed limit signs are opposite each other, attempt to make the change as close as possible to the actual speed limit signs but do not create a new segment if within 200 feet of a junction. When adding changing speed limits, choose the junction that is on the higher speed limit side. Basically if the change is going to happen slightly early or late, best to have a lower speed limit come earlier and a higher speed limit come later.
- Long term work zone speed limits may be mapped instead of the "ordinary time" speed limits. If placing a work zone limit, use Livemap to place a UR there, note that it is a temporary speed limit, and add [CONSTRUCTION] somewhere in the comment.
- If no speed limit sign is posted, the default speed limits in Delaware are
- Residential or business district: 25 MPH
- Two lane road: 50 MPH
- Divided highway: 55 MPH
Special notes
Delaware (especially NCCo) is really bad about signing speed limits on many roads. So even though the law says an unsigned road is above values, outside or rural areas of the state, that is probably not the case. May need to infer some speed limits based on signage pretty far down the highway.
Also do not assume every housing development is 25 MPH. Some localities have lower limits, like residential streets in Elsmere are 20 MPH.
Summary of National Guidelines
- Only map speeds found on regulatory white rectangular signs with black lettering.
- Do not map advisory speed limits (generally an orange or amber rectangular sign with black lettering).
- Where there are variable speed limits, map only the speed limit which is in effect most of the time during daylight hours (most hours of the day, days of the week).
- Do not map special speed limits for special vehicles. Waze only supports speed limits for private passenger cars.
Link to Delaware speed limit laws
Elevation
Delaware uses a real elevation method to set road elevations. This method sometimes requires the use of extra segments. This has the benefit of an enhanced look in the Live Map, and, more importantly, makes it easier to close a bridge or tunnel without affecting traffic to nearby homes and businesses.
