
Reading a reservoir that is half full
What the line on the wall of a reservoir tells you, and why half full can mean very different things in a dry year.

November 1, 2026 · 9 min
When a headline says shortage, what is actually short: the water, the pipes, the canal or the rain. Builds on “How to read a drought map”.
A short letter every Sunday: one piece of water news explained, with the numbers made small.

What the line on the wall of a reservoir tells you, and why half full can mean very different things in a dry year.

One tank, forty families and a timetable. How a valley decides who gets water and when.