Terms & disclaimers

What this is

Hydrohistorian is an advisory reading aid built on public data — Colorado DWR's HydroBase archive and REST services, USGS records, and the USACE National Inventory of Dams. It assembles, cross-checks, and visualizes those records; it does not create or administer them.

What this is not

• Not an administrative or legal conclusion. Colorado water is administered by the Division of Water Resources; every figure here is a screen or summary, never a determination. DWR's own records and tools (including AWAS) are the authority.
• Not a title opinion or engineering analysis. Do not rely on this site in place of a water attorney or professional engineer.
• Not guaranteed accurate or current. Upstream records are revised by the state; publication lags are real (diversion records publish ~a year in arrears); every page discloses its own sources, coverage, and freshness — read them. Analytical methodology has not yet had independent expert review, and that status is disclosed on the pages it affects.

Accounts & data

An account stores your email, a salted password hash, and the watch-list items (structures, gages, wells) you add. No payment details are stored on this site. We don't sell or share account data. To delete your account and its data, email the operator and it will be removed.

Beta status

This is beta software under active development. Features, data, and analyses may change or be withdrawn without notice. Use of the site is at your own risk; True Ascent Labs LLC disclaims all warranties and, to the maximum extent permitted by law, liability for decisions made in reliance on this site.