The Historic Flood Map is a GIS layer showing the maximum extent of individual Recorded Flood Outlines from river, the sea and groundwater springs that meet a set criteria. It shows areas of land that have previously been subject to flooding in England. This excludes flooding from surface water, except in areas where it is impossible to determine whether the source is fluvial or surface water but the dominant source is fluvial.

The majority of records began in 1946 when predecessor bodies to the Environment Agency started collecting detailed information about flooding incidents, although we hold limited details about flooding incidents prior to this date.

If an area is not covered by the Historic Flood Map it does not mean that the area has never flooded, only that we do not currently have records of flooding in this area that meet the criteria for inclusion. It is also possible that the pattern of flooding in this area has changed and that this area would now flood or not flood under different circumstances. Outlines that don’t meet this criteria are stored in the Recorded Flood Outlines dataset.

The Historic Flood Map takes into account the presence of defences, structures, and other infrastructure where they existed at the time of flooding. It will include flood extents that may have been affected by overtopping, breaches or blockages.

Flooding is shown to the land and does not necessarily indicate that properties were flooded internally.

Scottish legislation (Section 17) of the Flood Risk Management (Scotland) Act 2009 dictates that records of culverts must be created and maintained. Specifically: (1) Every local authority must prepare a map which shows (or more than one map which, taken together, show) relevant bodies of water and sustainable urban drainage systems in its area. (2) Each map must - (a) be prepared by such date as the Scottish Ministers may direct, (b) be prepared at a scale that the authority considers most appropriate, and (c) contain such information and be in such form as the Scottish Ministers may specify in regulations. (3) A local authority must, from time to time, review and where appropriate update the map (or maps) prepared for its area under subsection (1). (4) A local authority must make available for public inspection the map (or maps) prepared under this section for the time being applicable to its area. (5) In this section and section 18 - “relevant body of water” - (a) means - (i) a body of surface water other than a stretch of coastal water, or (ii) a body of underground water forming part of a watercourse (but not including a watercourse which is wholly underground), but (b) does not include sewers and drains which drain into sewers, “sustainable urban drainage system” has the meaning given in section 59(1) of the Sewerage (Scotland) Act 1968 (c.47). Most Local Authorities have contributed (natural) culvert data to the new OS MasterMap Water Network Layer either through providing data to the Scottish Government or through the James Hutton Institute. As this data is now live, a mechanism for managing/maintaining/updating this data needs to be put in place. SCOTS (Society of Chief Officers for Transportation in Scotland) have approved for this dataset to be managed by the Spatial Hub and any amended data can be uploaded (and potentially downloaded) before being shared with OSMA members and the OS. We have initially created a point and line data layer for the data we have been sent by some LAs ( the line format is obviously a more detailed and accurate depiction of the feature). This is the best available information at the time of submission and dimensions and routes may well be different in reality. The LA "culverts" as included in the OS MasterMap Water Network Layer is also available as a standalone layer.

Scottish legislation (Section 17) of the Flood Risk Management (Scotland) Act 2009 dictates that records of culverts must be created and maintained. Specifically:

(1) Every local authority must prepare a map which shows (or more than one map which, taken together, show) relevant bodies of water and sustainable urban drainage systems in its area.

(2) Each map must - (a) be prepared by such date as the Scottish Ministers may direct, (b) be prepared at a scale that the authority considers most appropriate, and (c) contain such information and be in such form as the Scottish Ministers may specify in regulations.

(3) A local authority must, from time to time, review and where appropriate update the map (or maps) prepared for its area under subsection (1).

(4) A local authority must make available for public inspection the map (or maps) prepared under this section for the time being applicable to its area.

(5) In this section and section 18 - “relevant body of water” - (a) means - (i) a body of surface water other than a stretch of coastal water, or (ii) a body of underground water forming part of a watercourse (but not including a watercourse which is wholly underground), but (b) does not include sewers and drains which drain into sewers, “sustainable urban drainage system” has the meaning given in section 59(1) of the Sewerage (Scotland) Act 1968 (c.47).

Most Local Authorities have contributed (natural) culvert data to the new OS MasterMap Water Network Layer either through providing data to the Scottish Government or through the James Hutton Institute. As this data is now live, a mechanism for managing/maintaining/updating this data needs to be put in place. SCOTS (Society of Chief Officers for Transportation in Scotland) have approved for this dataset to be managed by the Spatial Hub and any amended data can be uploaded (and potentially downloaded) before being shared with OSMA members and the OS.

We have initially created a point and line data layer representing the data we have been sent by some LAs. However, we really need line data in order for it to be merged into the OS MasterMap Water Network Layer data in due course.

The LA "culverts" data as included in the OS MasterMap Water Network Layer is also available for LAs to download and use as part of this dataset