Field assessment tools
Tools of the Trade
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Topographic and county map
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Compass
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Clipboard, pen, and paper
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File folders in which to collect Information on each site
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pH tester
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Flow measurement devices
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Camera
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Macroinvertebrate keys
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Pocket-sized electrical conductivity meter
Maps are excellent reference and planning documents, but when it comes to pinpointing AMD sources, the best method is to find the sites in the field, locate them on a topographic map, take water quality samples, estimate volume or discharge amounts, and enter the information into your database.
Topographic Maps
Before you conduct your watershed assessment, you will need to obtain topographical maps. "Topo" maps show the "lay of the land" with their detailed contour markings, making it easy to identify hills, ridges, waterways, roads, and other features. Each map measures about 18 x 20 inches and covers an area of about 7 miles by 8.5 miles. The production dates of these maps vary across the country, so be sure to note when your maps were printed. If they are very old, be alert for possible differences in road routes, buildings, and other features.
Two types of maps should be used to assess the watershed: a county highway map and a U.S. Geological Survey (USGS) 7.5-minute topographical map. The county highway map provides a detailed layout of roads, creeks, and other landmarks of the area and is useful for finding general regions to be investigated. The USGS topographical maps are used to delineate watershed bound aries and to identify sources of water, drainage ditches, creeks, rivers, some mine sites, structures, power lines, pipelines, ponds, and other features.
Testing Equipment
Basic test kits for pH can be purchased from any national firm for less than $75, with some of the color comparator pH kits priced in the $30 range. The best pH testers are the newer microprocessor-based units, which fit easily in a shirt pocket and can detect changes down to one-tenth or even one-hundredth of a pH standard unit. They cost $45 to $100, and display readings on a small digital screen. A pocket-sized conductivity meter is another good investment for field testing and is used to measure the amount of dissolved metals found in water samples. Conductivity refers to the ability of an electric current to pass through the water more quickly due to the presence of dissolved solids.
If you decide to do the testing yourself, it is a good idea to involve professionally trained partners, agency staff, or volunteers so that the readings are taken in the right places at the right times, and good records are kept of the sampling stations and results.
Bug Cards
In addition to visual observations, an effective water
quality assessment tool for field volunteers is a simple pictorial key to stream
insects and crustaceans. The Izaak Walton League of America publishes an
excellent "bug card" printed on both sides of a notebook-sized sheet of poster
board. The organisms on the key are grouped according to their pollution
tolerance.