The EACSD format stores all the data that is required by the major modelling software packages to build 1D (in bank) flood models. It is an ASCII format that is open and independent of survey and modelling software. As well as being machine readable, it has also been written so that humans can read it easily too.

The EACSD was conceived in 2011, as a standard format in which to store channel survey data, making it easier and cheaper to re-use expensive surveys. Whilst it was clearly of benefit to the Environment Agency it was not seen as so beneficial to the modellers and was not therefore widely adopted. The revised version, v3.2, was developed in conjunction with survey and modelling software developers, flood modellers and surveyors and incorporates several features that will result in dramatic gains in productivity. This revision (v3.33) includes clarification and minor revisions and upgrades to the validator to trap more errors.

The revised EACSD includes four main additional features that will improve the productivity of flood modelling:

• The format stores information about vegetation and bank and river bed material which will enable modellers to compute Mannings roughness values automatically across each and every section. The classifications are simple enough to be understood and implemented efficiently by field surveyors who will enter the data at the same time as observing cross-sections.
• The format also stores data about standard structures which can be read automatically into modelling packages. This replaces a time consuming manual process and significantly reduces manual input errors.
• The format enables the bank line to be defined, including breaks in the bank for incoming ditches and natural low points. Definition of the bank line is now more important due to the adoption of 1D/2D linked modelling.
• For many projects, the client requires modelling with and without flood defences. EACSD caters for this by recording the crest lines of defences as separate entities.

Jacobs has developed their Flood Modeller software to read the new format directly.

To keep data inconsistencies to a minimum, Jacobs have developed the online EACSD Validator. Surveyors will be required to run their EACSD files through it, correct any errors and provide the certificate of conformance with their data to the end client.