Percentage of Surface Drinking Water from Intermittent,
Ephemeral or Headwater Streams in Alabama
Legend: This map highlights
regional patterns of
dependence on intermittent,
ephemeral, and headwater-
streams for surface drinking
water in Alabama. In
Alabama, 10,239 total miles of
streams provide water for
surface water intakes
supplying public drinking
water systems; of this, 5,552
miles, or 54%, are
intermittent, ephemeral, or
headwater streams. Over 2.6
million people in Alabama
receive drinking water from
public drinking water systems
that rely at least in part on
intermittent, ephemeral, or
headwater streams. This
analysis compared the stream
length of intermittent,
ephemeral, and headwater-
streams to total stream length
within all mapped Source
Protection Areas (SPAs) for
each county. A SPA is an area
upstream from a drinking
water source or intake that
contributes surface water flow
to the drinking water intake
during a 24-hour period. This
is based on data that generally
do not include streams less
than one mile in length.
Intermittent streams are
streams containing water for
only part of the year.
Ephemeral streams flow in
response to precipitation
events. First-order streams
have been used to represent
headwater streams.
Data Sources: National
Hydrography Dataset Plus at
medium resolution; Federal
Safe Drinking Water-
Information System 4th
Quarter 2006 Data.
7
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Huntsville
Decatur
Birmingham
Hoover
Tuscaloosa
Montgomery
fDothan
Key;
Intermittent, ephemeral and
headwater stream miles as a
percentage of total stream miles
contained in all SPAs for a given
county
Mobile
0%
34% - 44%
45% - 56%
57% - 69%
70% -
87% - 100%
No Data

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