It doesn't look like an official ACHD sign though, it looks like an informational sign.

Is "Access Road" really the name of the road, or is it just a description?

It looks like you marked some residential roads as service roads. Do you know something I don't?

As far as I'm aware, this is the mouth of the canal.

I noticed that you removed is_in=* from objects, but not subkeys such as is_in:country_code=*. Is there any particular reason for that, or did Osmose not catch it
?

I'm not completely certain, but I feel like at least some of these aren't culverts and instead they have a bridge going over them. It's hard to define with canals.

Thanks for letting me know! I'll add Powell Lateral as an old name for the canal.

Where did you get the name from? I've always known the canal as Powell Lateral.

I noticed some of the buildings in this and other changesets by you have the tag building=building. What does that value mean?

In the future, can you make sure you use more informational changeset comments? '*' doesn't tell me much about your edits.

Is this a path connecting a residential neighbourhood to a main road? I imagine it should be tagged access=private, not access=no. If it's for emergency services, access=emergency would be more appropriate. access=no makes sense for places such as Area 51 but it feels too strong for this scenario.

I imagine these houses have square corners. When mapping buildings with square corners, be sure to hit Q when you're done drawing to orthogonalise the shapes.

Is access really no? For a school access=private seems more appropriate.

I imagine there are (or were) plans to develop the area and they built it ahead of time. Just my thought.

Ditto for Disneyland Railroad and some amusement rides.

Thanks for adding some culverts; sometimes I get too lazy to map those.

The text is available in the Library of Congress.

I found it in a 1900 Boise City directory on Ancestry.com

Not sure what happened to the changeset comment. I added some detail to the Boise River and added some ponds.

Seems like a good call.