[Imports] Proposed import: Surrey, BC waterways

Paul Norman penorman at mac.com
Thu Oct 6 05:49:00 BST 2011


Back in April in
http://lists.openstreetmap.org/pipermail/talk-ca/2011-April/003929.html I
proposed importing data from Surrey, BC to replace the current OSM waterway
data for the city, which is derived from a NHD import. The license and
accuracy of the data is not an issue, the only questions that arose were
around the mapping of roadside drainage ditches.

 

The accuracy of the Surrey data is unquestionably better than the existing
OSM data. The NHD data includes streams that were paved over 25 years ago.

 

In summary, the import would consist of four categories.

 

1.       Streams. These typically meander, are in forested areas, are
natural, and have names. They are often nutrient-bearing for fish.

2.       Rural and agricultural ditches. These are long, straight, and
sometimes have culverts.

3.       Ditches in suburban areas. These are broken up by culverts and
eventually drain into the storm drain system.

4.       Culverts. These are in a separate file, and join the breaks
together.

 

At the time, no one was certain if adding ditches would cause the area to be
unwieldy to edit. Over the last couple of days, I have been mapping in
Queensborough, an area with very similar ditches.

 

http://www.openstreetmap.org/?lat=49.19043
<http://www.openstreetmap.org/?lat=49.19043&lon=-122.9372&zoom=17>
&lon=-122.9372&zoom=17 is the area.

 

Ditches can be found on Lawrence, Wood south of Ewen, Boyne, Pembina north
of Ewen, Fenton and Johnston.

 

I have found that the ditches are not a problem when editing the area.
Adding the ditches takes some time to correctly split at culverts, but the
ditches to be import are already split.

 

The blue waterway=ditch lines are subtle on the gray landuse=residential
background and not overwhelming. I also looked at the osmarender and Open
Mapquest renderings, as well as an assortment of cloudmade renderings.

 

What I propose to do is process updated versions of the files and post them
for review. I have some old sample waterways at
http://maps.paulnorman.ca/surrey/samplewaterways.osm but additional work is
required, and I intend to use the latest shapefiles.

 

The waterways will be tagged with start_date, source, waterway, an ID in the
surrey:* namespace and the nutrient/fish status in the surrey:* namespace.

 

The nutrient/fish statuses are documented on
http://cosmos.surrey.ca/Geocortex/EssentialsExternal/Web/Metadata/metadata_e
xternal.html#drnFishClassifications

(broken HTML may be present)

 

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/imports/attachments/20111005/111a944f/attachment.html>


More information about the Imports mailing list