For the past few months, C-Lab has been hard at work collecting, managing and analyzing data pertaining to vacant land in LA. With data Community Health Councils and the LA Neighborhood Land Trust have acquired, the publicly available data on the Los Angeles County GIS Data Portal, and information from different city and county departments, C-Lab has created one giant database that provides a clearer description of LA’s vacant land than has been previously understood. While an on-the-ground assessment to identify all of LA’s vacant land would be ideal, doing so in a place that’s nearly 470 square miles in size is neither feasible nor practical.

To build the database, we first identified the lots categorized as vacant in the County Assessor’s data. This includes both publicly owned lots controlled by city, county, state, and federal agencies, as well as privately owned land. The County Assessor is responsible for determining property tax bills. While valuing LA County’s more than two million individual parcels, the Assessor also determines each property’s current use. “Vacant” is one such use. However, we have encountered a number of difficulties along the way with this data set. For instance, the use codes are not always up-to-date and we have noticed that a large percentage of the parcels labeled as vacant in fact have buildings on top of them. We are working towards refining this data to reflect a more accurate account of vacant lots in the city. While not 100% reliable, the data set does offer a strong foundation in which to build more reliable data.

We’ve also organized these lots based on their attributes. For a more comprehensive understanding of vacant lots in the city, we’ve added several other data sets: lots designated as part of the City’s weed abatement program, easements under power transmission lines, available side lots, and some data that will help verify if a vacant lot on paper is truly vacant. In the future, this data and mapping will continually be refined. Data on vacant land is highly dynamic and depends on when the data was collected. A lot that is vacant today could have a building on it in a month. Once our initial map is released, local organizations and individuals will be able to update the LA Open Acres map to help “ground-truth” the data.


Property Owned by the Department of Public Works (Google Images)

We’re continuing to include other data that will help identify vacant opportunity sites. Weed Abatement data can us identify which privately owned vacant lots are considered by the City to be abandoned. This could be symptom of property neglect, or perhaps tax-default, which could provide clues for local organizations and organizers. Some people also think Weed Abatement lots can be used as a measure for blight. We are examining easements of land under power transmission lines. These parcels are unused, other than the proportionally tiny footprints of electric poles, so they represent great potential to be transformed into usable space. People can negotiate with the power company for access to the space, like the group at Stanford Avalon Community Garden has done.  Parcels that are part of the Side Lot program are included in our database as well. These give landowners adjacent to these parcels the special right to purchase the land — in some instances, for as little as $200!


Stanford Avalon Community Garden. Photo by Ann Summa for L.A. Times

We are also categorizing lots by their Council Districts, Community Plan Areas and Neighborhood Councils, and will produce a map for each category. This will allow neighbors to better understand the nature of the vacant lots in each area of the city, and will be powerful tools for community organizations and members of city government to inform policy change.

We currently estimate that there are between 950 and 1,300 acres of vacant public land in the City of Los Angeles. We have also found somewhere between 11,600 and 16,230 acres of vacant private land. We are still collecting, refining and analyzing data, so these estimates are likely to change. We look forward to sharing some of our findings with you in the months ahead!