DATA INFORMATION FOR PERENNIAL STREAMS COVERAGE (updated)
CATEGORY ............. 
LAYER NAME ........... Perennial Streams
SHAPEFILE NAME ....... PStreams.shp
DATA EXTENT .......... Pima County (excluding Tohono O'odham Reservation Lands)
DESCRIPTION .......... Displays investigated perennial streams in Pima County (see perennial definition)
LAYER TYPE ........... Line
FEATURE COUNT ........ 58
SCALE ................ 
REGISTRATION ......... Pima County Land Information System (State Plane 27)
KNOWN ERRORS ......... Undetermined
SOURCE NAME (1) ...... Pima Associations of Governments
SOURCE DATE (1) ...... 2000
SOURCE SCALE (1) ..... 
SOURCE NAME (2) ...... 
SOURCE DATE (2) ...... 
SOURCE SCALE (2) ..... 
DATE OF LAST UPDATE .  November 2000

Field Summary:

ID: ........... Unique Identifier
PreachID: ..... Perennial Reach Identifier
R_Name: ....... Stream Reach Name
Loc_gen: ...... General Location Description
Loc_trs: ...... Township/Range/Section for Stream Reach
Watershed: .... Hydrologic Unit Code (HUC) and Watershed Name
Topo: ......... Name of USGS Topographic Map referenced
Q: ............ Known Flow (cubic feet/sec)
Desig_use: .... ADEQ Designated Use
Tree_spec: .... Tree Species noted in various references for the Reach Area
Tree_seedl: ... Seedling Tree Species noted in various references for the Reach Area
Tree_matur: ... Mature Tree Species noted in various references for the Reach Area
Tree_old: ..... Old Tree Species noted in various references for the Reach Area
Envfeature: ... Notable Environmental Features for the Reach Area
References: ... References used in determining perennial reach and attributes
Certainty: .... Level of Certainty ranked by levels 1-3.  (3) denotes a high level of certainty for information shown, and (1) denotes a low level of certainty for information shown
Notes_flo: .... Notes regarding flow characteristics such as end of flow observations
Notes_obs: .... Notes regarding general observations noted in reach area

Definitions:

Definitions of perennial, intermittent and ephemeral streams were obtained from United States Geological Survey Water-Supply Paper #1541-A (Langbein and Iseri, 1960):

Perennial:  	one which flows continuously;
Intermittent:  	one which flows only at certain times of the year when it receives water from springs or from some surface source such as melting snow in mountainous areas;
Ephemeral:  	one that flows only in direct response to precipitation, and whose channel is at all times above the water table.