Questions
Frequently asked
What this is, where the numbers come from, and what we will not say.
Where does the data come from?
Public sources only: reservoir storage from the US Bureau of Reclamation, streamflow from the USGS, drought class from the US Drought Monitor, and allocations as announced by the operating agencies. Every page names its source.
How often is it updated?
The underlying data is pulled daily. A weekly brief reads what moved over the week and goes out once a week. Each page shows a Last updated date so you know how fresh the reading is.
Do you forecast storage, runoff, or allocations?
No. We report what the public record shows and how it compares to the prior five years. We never predict future storage, runoff, or allocation percentages.
What does "below normal" mean?
Normal is the median value for the same calendar week over the prior five years. Below normal means today's value is under that median. The exact percent is shown on every page; nothing is left to a sense of the season.
Which reservoirs and basins do you cover?
Major western reservoirs operated by the US Bureau of Reclamation across the Colorado, Columbia, Missouri, Rio Grande, Great Basin, and California systems, rolled up by river basin. State-operated reservoirs that are not in the federal data set are not yet included.
Is this investment, legal, or water-rights advice?
No. The Watershed is a reading of public data for operators. It is not investment, legal, or water-rights advice. Decisions are yours to make with your own counsel and the primary agency data.
Can I get the weekly brief by email?
Yes. The brief is free and goes out weekly. Subscribing is the best way to catch what moved without checking the board yourself.