Constraint calendar

Month by month, what held Delta exports below capacity, and the Old and Middle River index that the fish rules are written on. Click a month to see its days.

Water year by month
Click a month for its figures.
Table of the same figures (text twin)
Old and Middle River index
CDEC station OMR, the tidally filtered index (cfs; negative is flow toward the pumps). Shaded days had an OMR restriction in force under the biological opinions or the incidental take permit. The dashed line is the common -5,000 cfs limit.
daily OMR indexOMR restriction in force-5,000 cfs
Monthly summary of the OMR series (text twin)

Sources. Binding reason and days by reason: the Delta Export Constraints dataset on this site (Layer 2 regime calendar 1929 through water year 2025, Layer 3 rule) over DWR Dayflow. OMR: California Data Exchange Center station OMR, sensor 41 (Old and Middle River tidally filtered index), 2007 to the present; the deprecated series built from the Old River near Tracy gage is never used here. Sacramento Valley water-year type: CDEC water-year classification, served by the Water Supply Live set on this site.

Method. A month’s binding reason is the most common daily reason in that month. OMR restriction days come from the regime calendar, which records the rule in force, not the day’s operating target; the regime calendar ends 2025-09-30, so later days carry the OMR value only. Full rules: definitions .

conciseVerbosity is an independent personal project; the views and tools here are separate from the organizations I serve.