January 04, 2015

“DC Great Streets: A Street-level Survey Using OpenStreetMap”

Background

Conducting a street-level survey is a great way to get students acquainted with local land use and land cover while learning important technical skills in the OpenStreetMap environment. The objective of a survey is to make a field-level determination of how the property or building is being used, create a geo-located photo survey of the streetscape, and add those features to OpenStreetMap. In the paragraphs below, we discuss the rationale for a street-level survey, outline the basic mapping activities, and offer pointers for your street-level survey.

Rationale

In late 2014, MappingDC began a collaboration with the DC Great Streets program to conduct a street-level survey in the twelve DC Great Streets corridors. The DC Great Streets program dispenses capital improvement grants to small businesses in these corridors to boost neighborhood economic resilience and help create lively urban centers around the city. Once a month, MappingDC hosts a mapping party in or along one of the corridors where we gather data in the field, upload, and edit the data in OpenStreetMap. The project is evolving with an emphasis on creating service learning opportunities for young adults that meet the needs of the DC Great Streets program.

Conducting your own street-level survey

Tools you’ll need

1. Mapillary: To create the streetview, we use Mapillary, a lightweight app that you add to your smartphone. So, before you get started, download and install Mapillary. Also review the tips and techniques on the Mapillary page so you take good, usable photos.

2. Field Papers: We use Field Papers to make a paper map of the streets, which we annotate in the field. Print out large-scale maps of your area of interest so you can annotate liberally and legibly. There is a very good Field Papers how-to on the OpenStreetMap wiki which shows how to use Field Papers for field data collection.

Workflow

The workflow:

1. Conduct field work
2. Return to base and begin editing in OpenStreetMap
3. Upload photos to Mapillary site
4. Review work for completeness and accuracy

Form teams for field work:

• Two teams of two or three people, one team on each side of the street. One person records basic information about the property or building (e.g. name, address, phone, website, etc.), the second person records takes photos. A third person is useful to take supplemental notes, help navigate, but not essential.

Editing process

• Trace building outlines as necessary. There are often multiple businesses in a building so enter each business as a point and give it its own address.

• The Great Streets program has a simple rating system to help determine which properties qualify for assistance. Mappers tag each property with a rating, which the DC Great Streets program can use to assess property condition. You should refer to the building condition page on the OSM wiki for help in tagging building conditions.

• Follow the instructions on the Mapillary page for uploading your photos from your phone to the Mapillary site.

Lessons Learned

MappingDC and DC Great Streets program are still working on how to standardize the tagging scheme for building conditions so that they are useful to the program. We’ve also learned that some photos are not usable because they are blurry, too dark, washed out, or taken at a bad angle. We’re working on developing field techniques that will make for more consistently usable photo quality. Tactically, teams of three seem to work best, but plan on at least two per team.

For more information:

Mapillary provides detailed instructions

See also Elliott Plack’s diary entry on how he created a street-level survey on bicycle.

For more information on street surveys or DC Great Streets mapping parties, please contact Steven Johnson (sejohnson8 at gmail dot com).