Reference data analysis
What the year comparison shows for Lake Biel
Typical low point
429.02 m a.s.l.
January 1
Typical high point
429.44 m a.s.l.
May 14
Typical range
43 cm
Difference between daily medians
In the 1991-2020 reference period, Lake Biel's seasonal median is lowest on January 1 at 429.02 m a.s.l. and highest on May 14 at 429.44 m a.s.l.. The difference between these typical points is 43 cm. This describes the average seasonal cycle, not the largest individual fluctuation.
The 2026 curve currently contains 265 calendar days. On September 22 it shows 429.22 m a.s.l., which is 5 cm below that calendar day's median of 429.28 m a.s.l.. Compared with the same calendar day in 2025, the value is 3 cm lower.
Within the 1991-2020 reference period, the envelope reaches its highest value of 430.88 m a.s.l. on August 10 and its lowest value of 428.70 m a.s.l. on January 18. These are extremes of the displayed reference period, not all-time records.
The analysis uses the water-level series from Ligerz. Matching calendar days are compared, and the median is the middle value of the reference years. This classification does not replace flood warnings or local safety information.