Figure: 30 TAC §298.470(c)
PHDI Index for Calculating Hydrologic Conditions for all Measurement Points on the Brazos
River and its associated tributaries and the San Bernard River and its associated tributaries
GEOGRAPHIC AREA
DRY
AVERAGE
WET
UPPPER BASIN
less than -1.78
-1.78 - 2.18
greater than 2.18
MIDDLE BASIN
less than -1.95
-1.95 - 2.39
greater than 2.39
LOWER BASIN
less than -1.73
-1.73 - 2.13
greater than 2.13