WaterML exchange format

An XML standard for exchanging water observations, available as a return format on the USGS Water Services APIs alongside JSON, RDB and KML.

In this catalog it appears concretely: - USGS Water Services — "waterml (XML)". - same — "the joint USGS/EPA Water Quality service".

A label on a listing is not a deliverable. Teams that license on the strength of a product-name match routinely find the shipped files cover a narrower slice than they assumed, and backfilling history afterwards costs more than the license ever did.

The failure mode is concrete: the label appears in a listing, the delivered files tell a different story, and the gap surfaces mid-project when fixing it is most expensive.

You rarely have to take a vendor's word for it. 82.4% of the 1,744 datasets Datadory catalogs are free to access, and USGS Water Services lets you inspect the real artifact before any budget is committed.

Treat every claim of this attribute as testable:

1. Open USGS Water Services and confirm its record — "waterml (XML)" — against the files you actually receive.
2. Open same and confirm its record — "the joint USGS/EPA Water Quality service" — against the files you actually receive.
3. Pin down update cadence in writing. Across this catalog, 22.6% of 1,744 datasets refresh daily and 64 still arrive only through a manual request form, so ask exactly how fresh each release is.
4. Check whether definitions are verified at all. Field definitions are verified for 1495 of 1,744 datasets (85.7%), and any source you license should meet that bar.
5. Price the delivery route before the license. In this catalog bulk download is the most common access method (725 datasets) ahead of official APIs (574), and 379 sources still require scraping — a maintenance cost that lands on you, not the vendor.

See the term applied to real records: multi-utilities data, water-utilities data.

Adjacent concepts worth reading next: - Instantaneous Values service (IV) - RDB tab-delimited format