Construction of a year-round operating gauging station for sediment and water quality measurements of small watersheds

An automated year-round gauging station was installed at the outlet of a 0.8 km(2) (0.31 mi(2)) watershed located at the Agriculture and Agri-Food Canada Lennoxville Research Station in the heart of the southern Appalachian region of Quebec's Eastern Townships. Unlike other gauging stations in the province, the gauging station was designed to collect data during the winter-and snow-melt season. It consisted of devices to measure stream-flow, suspended sediment, bed lend, and such hydrometeorological variables as precipitation and temperatures of the dir, stream-water, and roil. Stream-flow rate was determined by measuring the water stage at fixed calibrated points using a custom-made nitrogen bubbler system and calibrated flumes. An automatic water sampler was used to take three composite samples of the stream-flow per day for suspended sediment concentration determinations. Over a duration of eight hours, each sample was composed of 100 samplings of 10 ml (0.03 in(3)) at 4.8 min intervals. A concrete 3.5 m(3) (124 ft(3)) sediment trap was installed in the stream bed for bed load measurements. The accumulated coarse sediments were measured after each important storm event during summer and on a seasonal basis through the rest of the year. A tipping bucket rain gauge was used for precipitation measurements. Electronic pressure and temperature sensors, and the tipping bucket, were connected to a data acquisition system coupled to a microcomputer that automatically recorded the data at predetermined time intervals.