Thursday, April 11, 2019

Mapping open space in Massachusetts, including private parcels

I have been thinking about access issues since I first noticed the signs in Estabrook Woods, warning trail users that the trails may be closed if people don't follow the rules (which are reasonable rules, in my opinion).  I have been walked, running, skiing, and biking in Estabrook since I first discovered the trails in 1998, not long after I moved to Boston.  I knew that the land there was largely private and I would love to have these trails remain open for the long term.

Someone recently asked me if a map or data of Chapter 61 exists and I looked and found one, held by MassGIS, the state agency charged with maintaining and distributing public geospatial data for the state.  (Find the links to the data and explanations at the end of the post.)  The map below uses this data.

Estabrook is primarily private land.  If you know where to look, it's a big patch of yellow on the map (P, for Private for profit) and outlined in blue.  A lot of that land is owned by Harvard University.  There is also the Pippen Tree Farm (L for Land Trust, color is sort of orange, depending on your screen), which has been the most emphatic about limiting which trails can be used on their land.  All of the private land is protected, and open, under Chapter 61, the Massachusetts law that gives favorable tax reductions if the land is managed for forestry and/or open to passive recreation.  Also see this explanation of the Chapter 61 regulations.  And the Town of Concord owns some parcels in the area.

After looking at Estabrook, I added my GPS track from the 2016 Diverged Ride out of Ride Studio Cafe in Lexington.  You can see this as a red line on the map that turns into red dots as you zoom in.  You can see that the ride largely stays on public land and sometimes on land protected by Chapter 61 (P and L among other categories - a full list of categories is below the map in this post).  At other times it is on roads or public right of ways.  I've been on several of their rides:


and always wondered what land we were on and how legal is was to be there.  The short answer is that the rides were either well researched or lucky in that they all seem to follow public or otherwise open land.  Check out the map.

One thing to note is the many small parcels that make up Minuteman National Historical Park.  Any guesses as to why the Park Service had to buy many small parcels to make this?

Another oddity: The land that the Reformatory Branch Trail runs on is public.  But the Bedford section of the Minuteman Path is owned by the town.  And the Lexington section is privately owned, at least according to the map.

The codes (FEESYM) in the map are likely to be unreadable on their own.  Here is what MassGIS says in the metadata (see link below):

F- Federal
S - State
C - County
M - Municipal
N - Private Nonprofit
P - Private for profit
B - Public Nonprofit
L - Land Trust
G - Conservation Organization
O - Other / None of the above (e.g.joint ownership)
X - Unknown
I - Inholding (a piece of unprotected property surrounded on all sides by a protected property or a recreational facility)
Unconfirmed:
1 - EOEEA or alternate state agencies
2 - EOEEA or non-profit
3 - EOEEA or municipality
4 - EOEEA or private landowner

You can download this data from MassGIS here.  And here is how they constructed the data model.  It isn't new data - I found a 2008 version that has fewer private parcels in the Estabrook area.  It is nice to know that these data are available to plan mixed terrain rides, if you aren't like Vandermark and have all of them memorized already.

And you should be aware that the final arbiter of boundaries are the survey descriptions and not these lines on a map.  As MassGIS said in the download/metadata page:

"These data are very useful for most statewide and regional planning purposes. However, they are not a legal record of ownership, and the user should understand that parcel representations are generally not based on property surveys."

And I will add that your GPS tracks are from an instrument with an accuracy of 3-5 meters and less under dense foliage.

The map on this page was made with Carto.  It is pretty easy to use although I couldn't see how to make layers transparent on the free version (please let me know how to if you know how to do this).  I can make a better map using Qgis but I don't have access to a server to make it public.  But you can download Qgis and export your Garmin tracks to GPX format and make custom maps at home.  Let me know if you want some help doing that.