Data Structures

ESR

ESR Data Structure

- refnum (string) - this is made up of a route specific prefix, a three digit incremental counter, plus the two digit year

- speed (object) - "Freight Speed / Passenger Speed" - single number if both are same, units and unrestricted line speed

- route (object) - all properties of the route

- du (object) - responsible Delivery Unit

- elr (object) - ELR of track segment impacted e.g. LTN1

- lor (object) - LOR properties

- location (string) - description of where the restriction is applied, should be "At X" or "Between X and Y"

- reason (object) - describes reason the ESR is imposed

- withdrawn (bool) - 0 = active, 1 = withdrawn

- whenimposed (string) - W3C format date time string, updated during amendment

- etc (null|string) - if set this is a W3C format date time string

- whenwithdrawn (null|string) - if withdrawn === 1, W3C format date time string

- lines (array) - object for each "line". A "line" is the combination of ELR + TrackID

- elr (object) - as above

- trackId (int) - e.g. 1100 = Up Main

- direction (string) - "Up Direction" | "Down Direction" (yuk)

- linedescription (string) - can be driven by trackId or overridden by Controller

- routeheader (string) - "Primary Line" | "Additional Line"

- boards (array)

- type (string) - short name (no spaces)

- description (string) - long name

- elrId (int) - copied from line

- trackId (int) - copied from line

- miles (int) -

- chains (int) - 0 >= X < 80

- serialNumber (string) - not currently used

- marker (GeoJSON)

- references (object)

- updated_at - time of last database change

Example Response

{
  "id": 5,
  "refnum": "AICC 001.26",
  "speed": {
    "value": "40",
    "unit": "mph",
    "linespeed": "120"
  },
  "route": {
    "routecode": "EA",
    "routename": "Anglia",
    "shortname": "AICC",
  },
  "du": {
    "name": "Ipswich",
    "routeId": 2,
  },
  "elr": {
    "elrcode": "LTN1",
    "elrdescription": "LIVERPOOL STREET - TROWSE LOWER JN",
  },
  "lor": {
    "lorcode": "EA1011",
    "lordescription": "SEVEN KINGS TO IPSWICH",
  },
  "location": "At Colchester South Jn",
  "reason": {
    "reason": "Structural - Station",
  },
  "lines": [
    {
      "elr": {
        "elrId": 668,
        "elrcode": "LTN1",
        "elrdescription": "LIVERPOOL STREET - TROWSE LOWER JN",
        "active": true
      },
      "trackId": 1100,
      "routeheader": "Primary Line",
      "direction": "Up Direction",
      "linedescription": "Up Main",
      "newStyleBoards": true,
      "boards": [
        {
          "type": "commencement",
          "description": "Speed Indicator (Commencement)",
          "elrId": 668,
          "trackId": 1100,
          "miles": 50,
          "chains": 75,
          "serialNumber": null,
          "marker": {
            "type": "Feature",
            "geometry": {
              "type": "Point",
              "coordinates": [
                0.876876605,
                51.90208042
              ]
            },
            "properties": {
              "type": "commencement",
              "description": "Speed Indicator (Commencement)",
              "elrId": 668,
              "trackId": 1100,
              "miles": 50,
              "chains": 75,
              "serialNumber": null
            }
          }
        },
        {
          "type": "termination",
          "description": "Termination Indicator",
          "elrId": 668,
          "trackId": 1100,
          "miles": 49,
          "chains": 75,
          "serialNumber": null,
          "marker": {
            "type": "Feature",
            "geometry": {
              "type": "Point",
              "coordinates": [
                0.85427535,
                51.89894058
              ]
            },
            "properties": {
              "type": "termination",
              "description": "Termination Indicator",
              "elrId": 668,
              "trackId": 1100,
              "miles": 49,
              "chains": 75,
              "serialNumber": null
            }
          }
        }
      ]
    }
  ],
  "whenimposed": "2026-03-18 11:42:06",
  "etr": null,
  "withdrawn": false,
  "whenwithdrawn": null,
  "references": {
    "fmsnumber": "123",
    "ccilnumber": "23645657",
    "tsrreference": "",
    "tdanumber": "",
    "wo": "",
    "rdms": "",
    "trustcode": "",
    "owner": ""
  },
  "updated_at": "2026-03-18 11:42:06"
}