The purpose of this resource is to have students learn to use the hydrology instruments and collect the hydrology data accurately. In the classroom, students practice using the instruments or kits for protocols, exploring the range of measurements and sources of variation and error. Full description.

The purpose of this resource is to measure the salinity of the water using a salinity titration kit. Students will measure the salinity of saltwater using a salinity titration kit. Full description.

The purpose of this resource is to measure the salinity of the water at your hydrology site. Students use a hydrometer to measure the specific gravity of the water sample, and use a thermometer to measure the temperature. With these two values, students will use tables to determine the salinity. Full description.

The purpose of this resource is to determine the transparency of water. Students measure water transparency at their undisturbed study site using a transparency tube or Secchi disk. Full description.

The purpose of this resource is to help students understand that some substances can be identified safely with your senses. Students will investigate how they use their senses for observation and why we use instruments to collect data. Full description.

The purpose of this resource is to measure the temperature of a water sample. Students use an alcohol-filled thermometer or meter to measure the temperature of water. The meter requires calibration before use; the accuracy of the thermometer needs to be checked before use. Full description.

The purpose of this resource is to become familiar with the hydrology of your locale. Students will study and visit the Hydrology Study Site, conduct a visual survey to discover information about local land cover, water quality, and document their findings. They will use this initial investigation to raise questions about local land cover and/or water chemistry issues that may require further ... Full description.

This USGS site contains very useful descriptions about many aspects of ground water. The major topics include Ground Water, How Ground Water Occurs, Quality of Ground Water, Appraising the Nation's Ground-Water Resources, and a Glossary. This is a non-technical site, designed for use by the general public. Several charts and diagrams are also included in this site. Full description.

The National Water Information System (NWISWeb) provides real-time and historical data on water flow, water levels, and water quality for approximately 1.5 million sites in all 50 States, the District of Columbia, and Puerto Rico. The types of data collected generally fit into the broad categories of surface water and ground water. Surface-water data such as gage height (stage) and stream flow (discharge) ... Full description.

These illustrations and accompanying descriptions outline the basic concepts of groundwater aquifers. Users may learn definitions of basic terms (aquifer, confined, unconfined, water table) and see how the properties and orientations of rock layers act to accumulate water, which can then flow out or be pumped out by a well. Full description.