Thursday, May 1, 2014

The Good and Bad of Parcel Search Tools

During my County Council Whatcom County presentation on geology hazards (HERE) I put up this slide at the very end regarding policy and geology hazards.
The one area I was critical of the county was regarding the county online property and parcel map search. Ralph Schwartz was in attendance and picked up on the issue ( and

I used Jefferson County as an example of a parcel search tool. 

Typing in the address or the tax number will take you to assessor data information about the property in question, but if you click on maps you get this page:

The page gives you a choice of maps. Click on the Critical Areas map and you get this:

 A county map with a tool bar and layers that can be turned on or off depending what your interested in. So if I turn on LiDAR towards the bottom of the layers list and zoom into an area I am interested in I get this on the Toandos Peninsula along the west shore of Hood Canal.

This great for geologists, but the images also help any perspective property owner or an owner wanting more information about the lay of the land. The north-south glacial striations can be seen as well as deeply incised ravines as well as some deep-seated landslide activity. The tool bar allows one to measure distances and click points to find the elevations.

If you prefer not having a bare earth image from the LiDAR you can click on an aerial image from several dates typically going back to the early 1990s. And if you want to see where streams might be located click that.

A forested landscape showing the location of the lots and streams including streams thought to have fish. Important information when in the early stages of thinking about developing a property.

But how about the geology hazards? Click off the aerial photo and click on Landslide Hazard and you get this:
Yellow is low landslide hazard, orange is medium and red is high. Green are lots where a landslide hazard has been identified. No color means the location is thought to not be in a landslide hazard.

The designations are not absolute. The map is meant to be a screening tool to alert someone that there may be an issue. There is no doubt that the screening tool could be improved, but the green zones indicate that as information becomes available the County tweaks the map. Those green lots have all had some sort of geology investigation or report or observation that there has been landslides at those sites. The landslide activity only impacted a portion of the properties.

In my own notes as a geologist I have already tweaked this map using LiDAR plus some on the ground work and would add a bit a red swatch across some of the yellow area.

Another layer to try is Parcel Tags. These are parcels that have got some attention and could be viewed as worth a careful look at the permits.

If you click on the lot with the "i" (information tool) you can get some information as to why a parcel was tagged.

In the case of one of the red parcels, the parcel was tagged as having a geotechnical report. The report places some constraints on the lot as to where the home can be located, how storm water is managed, septic location etc. The idea is the potential buyer can see the report'

The Jefferson County system is by no means perfect, but it allows property owners to be much better informed. The above example relates to a recent small project I did. i buyer was looking at a lot in the area and noted that there were red tagged lots with geotchnical reports. He called me because I had written one of the reports or two or three (kind of my niche area). He was already well informed and the fact that there was deep-seated translational landslide on the property he was interested in was not a surprise.

There are other very good parcel search tools. I have been using some for so long that I am not sure how easy they are to use as I have them kind of figured out. But I have always like the Jefferson system. Clallam has essentially the same program, but has even more information on the maps. King County I Map is very good and Thurston County has a nice system as well at least for my purposes. And yes, Whatcom is terrible as is Island.  


Geoff said...

I am having my students who have the Oso IDT work on this type of thing and you did it for them! Thanks (they appreciate it).

Wayne said...

I agree that some counties have nice, useful parcel information tools (and others don't). I also have seen where some county's charge extra for "premium" web viewers (Clark and Pierce County do this, even though I'm pretty sure it's against the state's open records laws).
I think the State should step in and offer to create a single uniform site for this kind of data instead of having 39 counties trying to deal with this problem separately.

christine said...

Thanks for the tips on using. JMAP. I had been using it, but not to its full potential. Your screenshots and instructions were very helpful.