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Schweizerische EidgenossenschaftConfédération suisseConfederazione SvizzeraConfederaziun svizraFederal Office for the Environment FOENOpen Data (OGD)

API versions

The API is offered as a single GraphQL endpoint at https://data.bafu.admin.ch/api. There is no version segment in the URL and no version request header; every client uses the current schema. Notable changes to the schema and the data are recorded in the version history below. Versions follow Semantic Versioning (Major.Minor.Patch): the major number increases on a breaking change, the minor on a new backward-compatible feature, and the patch on a backward-compatible fix. The version records how the schema has evolved and is not selected by clients.

Version history​

Legend: Major a breaking change that may require client updates. Minor a new, backward-compatible feature. Patch a backward-compatible fix.

VersionRelease dateChangeDescription
1.2.0November 2026MinorNew dataset Life cycle inventory database BAFU:20XY (economy_consumption.lca): the impact factors of the FOEN life cycle inventory database, per version. The deliveries of a dataset are processed one at a time, in the order in which they arrive. An older delivery no longer overwrites a newer one.
1.1.02026-09-15MinorColumn descriptions in German and English. The filters of the generic download offer selection lists of the values present. Fixes: the timestamps nawa_sampling_start_ts and nawa_sampling_end_ts of water.nawa_trend are given in UTC; previously they held Swiss local time and were one hour late in winter and two hours late in summer. 343 457 duplicate rows are removed. The daily, monthly and yearly values of water.observations are loaded for the correct period; their timestamp marks the start of the period in fixed Central European Time (UTC+1), given in UTC.
1.0.02026-07-03MajorInitial public release with the water.observations and water.nawa_trend datasets.

Schema evolution​

The schema is extended over time as new datasets are published. These changes are additive and backward-compatible:

  • new namespaces, types and fields,
  • new filter fields on existing types.

Additive changes do not affect existing queries. A query that selects an explicit set of fields continues to return those fields when new ones are added elsewhere in the schema.

The current schema can be inspected at any time through GraphQL introspection — for example via the GraphiQL Explorer.

Breaking changes​

Changes that are not backward-compatible — such as renaming or removing a field or changing a field's type — are avoided wherever possible. Should such a change become unavoidable, it is announced in advance on this page so that affected clients can adapt.