Survey Markers

Data is captured by Iowa DOT surveyors and loaded via the Survey Portal. All populated data comes directly from the field data collection units. X, Y, and Z fields are projected in the system listed in the "Coordinates System" field using the datums listed in the Horizontal Datum and Vertical Datum fields. Contact information for each point can be found in the "Surveyors Name" field. If you have any questions about the general data, contact the Survey Manager in the Office of Design.

Querying over HTTP

Splitgraph serves as an HTTP API that lets you run SQL queries directly on this data to power Web applications. For example:

curl https://data.splitgraph.com/sql/query/ddn \
    -H "Content-Type: application/json" \
    -d@-<<EOF
{"sql": "
    SELECT *
    FROM \"mydata-iowa-gov/survey-markers-srqk-5uvp\".\"survey_markers\"
    LIMIT 100 
"}
EOF

See the Splitgraph documentation for more information.