Water Module »
Knowing where you are is just as important as the data you collect.
Many important wildlife observations were eliminated from the statewide database for the Gap Analysis, because there wasn't enough information to accurately locate the habitat on a map. A major problem occurs when a location is described based on street names and local landmarks. For example, a location described as "in my backyard, which is down the street from the Texaco station on the corner of 312th and Grand", is meaningless unless a city, street number, and street map are available. Even then, the Texaco station would not be identified on a street map.
Stream or lake names are important, but where you are monitoring is very important.
There are two consistent ways of recording locations: Using latitude and longitude
Using the Township, Range and Section (TRS) grids
- Latitude and longitude are marked on the U.S.G.S. maps. The U.S.G.S. has a program that prompts you for location information which will then provide the latitude and longitude.
- The DeLorme Atlas CD-ROM contains street locations and their corresponding latitude and longitude readings.
Take a look at this USGS query form.
You can find this and other websites under Internet Resources.
- Global Positioning Satellite (GPS) units have become cheaper and available to the general public.
The hand-held GPS units use satellites to locate a position on the ground and provide a digital read-out of the
latitude and longitude. Forests and canyons can interfere with the signal and prevent some units from locking on
to the satellites. GPS units work best in open country and on water.
- Every state west of the Mississippi has a TRS grid that is used by agencies.
There are some states east of the Mississippi that have created a TRS grid for their use. This is the standard way of recording a location in Washington State.
The Township numbers begin with 1 at the southern part of Washington State
and increase by one as you move north. The Township number is found on the left and right
edges of the U.S.G.S. 1:100,000 maps, and the DeLorme Washington State Atlas (available at all book stores).
Township 1 will be printed as "T01N" (Township 1 North).
The Range numbers begin along a meridian (a constant longitude line that passes through a given place and the terrestrial poles) that crosses Washington by the Puget Sound. Range numbers increase by 1 moving east or west from the meridian. The Range numbers are found on the top and bottom edges of the U.S.G.S. 1:100,000 maps and the DeLorme Washington state Atlas. Range 1 East will be printed as R01E. (The 1:24,000 U.S.G.S. maps print the TRS within the map body and not on the edges.)
Homeowners can find their TRS on their mortgage papers.
Each Township/Range consists of 36 Sections. Each Section is one square mile.
Section 1 begins in the northeast corner and the numbers increase as you move west. The next row of
Sections increases as you move east. Sections 1, 6, 31, 36 are printed on the U.S.G.S. 1:100,000 and
DeLorme Washington state Atlas maps. Grids for the 1:100,000 and DeLorme Atlas are included at the end of
these Guidelines. Use these grids to create transparencies to lay over your maps.
The Sections can be divided into halves: N-S, E-W or quarters: NW, NE, SW, SE.