Watershed Management Plan - Mason County

Chapter
Glossary 9
pH – A measure of the relative acidity or alkalinity of water. Water with a
pH of 7 is neutral; lower pH levels indicate increasing acidity, while pH
levels higher than 7 indicate increasingly basic (alkaline) solutions.
Planning Unit – A local group that is formed to assess water resources,
identify water needs, and recommend watershed management strategies.
Pool – A slower, deeper area of a stream channel. Fish use pools for
resting, rearing and refuge.
Riffle – A shallow, gravelly, faster-moving section of a stream in which
salmon find insects to eat and also use for spawning.
Salmonid – Fish species that are, or are related to, salmon, such as trout
and steelhead.
Saltwater intrusion – The invasion of a body of fresh water (including
groundwater) by saltwater, due to its greater density; in the context of
WRIA 16, this term refers to the movement of seawater into freshwater
aquifers along Hood Canal.
Stormwater – The water and associated material draining into streams,
lakes, or sewers as the result of rain or other storm.
Streamflow – The water discharge that occurs in a natural channel.
Surface water – All water naturally open to the atmosphere (such as rivers,
lakes, reservoirs, streams, impoundments, seas, estuaries, etc.) and all
springs, wells, or other collectors which are directly influenced by surface
water
Suspended sediment – That portion of the sediment load suspended in
the water column. Distinct from bedload, which is defined as the material
rolling along the bed. Relative size of the suspended sediment is
determined by flow characteristics, such as velocity.
TMDL – Total Maximum Daily Load: the maximum amount of a pollutant
that a waterbody can receive and still meet water quality standards. TMDLs
are typically set by government agencies.
Tributary – A smaller stream that flows into a larger stream.
Water purveyor – An agency or person that supplies water.
Water right – A legal authorization to use a predefined quantity of public
water for a designated, beneficial use.
Watershed – The land area that drains into a stream or other water body
(e.g., a lake or ocean); as such, WRIA 16 is not technically a single
watershed but a number of watersheds; WRIA 16 could also be considered
part of the Hood Canal watershed.
Final Plan for County Adoption – May 11, 2006 page 63