Section 298.455 - DefinitionsThe following words or phrases have the following meanings in this subchapter unless the context clearly indicates otherwise:
(1) Average condition--for all measurement points, the hydrologic condition that would occur approximately 50% of the time.(2) Climatic division--a geographic area defined by the National Weather Service.(3) Dry condition--for all measurement points, the hydrologic condition that would occur approximately 25% of the time and that is intended to represent the driest periods.(4) Lower Basin--the geographic area of the Brazos River Basin which includes all watersheds below Lake Whitney Dam, and the San Bernard River and coastal watersheds, and which is defined for the purpose of calculating hydrologic conditions as described in § 298.470 of this title (relating to Calculation of Hydrologic Conditions).(5) Middle Basin--the geographic area of the Brazos River Basin which includes all watersheds draining into the Brazos River and its tributaries downstream of Possum Kingdom Dam and upstream of Lake Whitney Dam, and which is defined for the purpose of calculating hydrologic conditions as described in § 298.470 of this title (relating to Calculation of Hydrologic Conditions).(6) PHDI--the Palmer Hydrological Drought Index, based on a scale from -6.0 to 6.0, and representing the severity of moisture conditions from extremely dry to extremely wet.(7) PHDI Index--a regional PHDI, calculated for the Lower Basin, Middle Basin, and Upper Basin, based on ranked values for a period of record from 1895 through 2010, and which is defined for the purpose of calculating hydrologic conditions as described in § 298.470 of this title (relating to Calculation of Hydrologic Conditions).(8) Spring--the period of time March through June, inclusive.(9) Sound ecological environment--characterized by fish, macroinvertebrate, and riparian vegetation species assemblages that remain relatively intact compared to historical records.(10) Summer--the period of time July through October, inclusive.(11) Upper Basin--the geographic area of the Brazos River Basin which includes all watersheds upstream of and draining into Possum Kingdom Lake, and which is defined for the purpose of calculating hydrologic conditions as described in § 298.470 of this title (relating to Calculation of Hydrologic Conditions).(12) Wet condition--for all measurement points, the hydrologic condition that would occur approximately 25% of the time and that is intended to represent the wettest conditions.(13) Winter--for all measurement points, the period of time November through February, inclusive.30 Tex. Admin. Code § 298.455
The provisions of this §298.455 adopted to be effective March 6, 2014, 39 TexReg 1416