Methods and systems for detecting a partial closure of a navigable element

1. A method of identifying navigable stretches that are potentially partially closed in a navigable network within a geographic area, the method comprising:

obtaining, by a server that comprises a processor and a memory, positional data relating to the movement of a plurality of devices along a navigable stretch with respect to time in a given time period;

determining that the given time period is a period of non-congested traffic flow for the navigable stretch;

using, by the server, the positional data to determine an average speed of travel along the navigable stretch in the given time period;

comparing, by the server, the average speed of travel to a free flow speed for the navigable stretch;

comparing, by the server, the average speed of travel to a threshold value; and

determining, by the server, that the navigable stretch is potentially partially closed when the given time is determined to be a period of non-congested traffic flow for the navigable stretch and when the average speed of travel is both lower than the free flow speed by a predetermined value and lower than the threshold value, wherein the threshold value is not set by reference to the free flow speed.

2. The method of claim 1 , wherein the obtained positional data comprises live positional data, and the method comprises using the live positional data to determine the average speed of travel along the navigable stretch in the given time period.

3. The method of claim 1 , wherein the devices are devices associated with vehicles.

4. The method of claim 1 , wherein the time period is a period in which the traffic volume for the navigable stretch is less than 50% of the average traffic volume for the stretch.

5. The method of claim 1 , wherein the given time period is a time period including a current time.

6. The method of claim 1 , wherein the navigable stretch is potentially partially closed when one or more of multiple lanes of the navigable stretch are closed to traffic flow, but one or more lanes remain available for traffic flow.

7. The method of claim 1 , wherein determining that the navigable stretch is potentially partially closed further comprises determining that the navigable stretch is potentially partially closed when the free flow speed exceeds a threshold value.

8. The method of claim 1 , further comprising excluding positional data relating to the movement of devices having speeds determined to be below a given threshold for a distance above a given threshold.

9. The method of claim 1 , wherein determining that the given time period is a period of non-congested traffic flow for the navigable stretch comprises determining that the given time period is a period having a traffic flow substantially lower than an average traffic volume for the navigable stretch.

10. The method of claim 1 , further comprising:

determining a type of vehicle associated with the positional data; and

removing, from positional data used to determine the average speed, positional data from specified types of vehicles, the specified types of vehicles being vehicles that are expected to travel at speeds that are lower than typical speeds for other types of vehicles.

11. A non-transitory computer readable medium comprising computer readable instructions which, when executed by at least one processor of a system, cause the system to perform a method comprising:

obtaining positional data relating to the movement of a plurality of devices along a navigable stretch with respect to time in a given time period;

determining that the given time period is a period of non-congested traffic flow for the navigable stretch;

using the positional data to determine an average speed of travel along the navigable stretch in the given time period;

comparing the average speed of travel to a free flow speed for the navigable stretch;

comparing the average speed of travel to a threshold value; and

determining that the navigable stretch is potentially partially closed when the given time is determined to be a period of non-congested traffic flow for the navigable stretch and when the average speed of travel is both lower than the free flow speed by a predetermined value and lower than the threshold value, wherein the threshold value is not set by reference to the free flow speed.

12. The non-transitory computer readable medium of claim 11 , wherein the obtained positional data comprises live positional data, and the method comprises using the live positional data to determine the average speed of travel along the navigable stretch in the given time period.

13. The non-transitory computer readable medium of claim 11 , wherein the devices are devices associated with vehicles.

14. The non-transitory computer readable medium of claim 11 , wherein the time period is a period in which the traffic volume for the navigable stretch is less than 50% of the average traffic volume for the stretch.

15. The non-transitory computer readable medium of claim 11 , wherein the given time period is a time period including a current time.

16. A system for identifying navigable stretches that are potentially partially closed in a navigable network within a geographic area, the system comprising:

at least one processor, the at least one processor configured to:

obtain positional data relating to the movement of a plurality of devices along a navigable stretch with respect to time in a given time period;

determining that the given time period is a period of non-congested traffic flow for the navigable stretch;

use the positional data to determine an average speed of travel along the navigable stretch in the given time period;

compare the average speed of travel to a free flow speed for the navigable stretch;

compare the average speed of travel to a threshold value; and

determine that the navigable stretch is potentially partially closed when the given time is determined to be a period of non-congested traffic flow for the navigable stretch and when the average speed of travel is both lower than the free flow speed by a predetermined value and lower than the threshold value, wherein the threshold value is not set by reference to the free flow speed.

17. The system of claim 16 , wherein the obtained positional data comprises live positional data, and the at least one processor is further configured to use the live positional data to determine the average speed of travel along the navigable stretch in the given time period.

18. The system of claim 16 , wherein the devices are devices associated with vehicles.

19. The system of claim 16 , wherein the time period is a period in which the traffic volume for the navigable stretch is less than 50% of the average traffic volume for the stretch.

20. The system of claim 16 , wherein the given time period is a time period including a current time.