2010-12-13_HYDROLOGY - M1980047 (2)

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Richard D. Piland & Associates Hydrology Monitoring Report 2008 • Operating Procedures The stream flow monitoring stations are operated year round at the Colony Tract. Station field trips are made at varying intervals depending on the time of the year. Normally station visits are made every two weeks with less frequent visits in winter and more visits during snow melt runoff or extremely rainy intervals. A station visit consists of recording the control device and stage on the recorder chart along with the station name, date, time, and remarks. Maintenance items covered would be to the recorder, removing mud from the control or stilling well, and preparing the station for winter. Monitoring stations consist of a Stevens Type A Model 71 stage recorder; a control device, such as a Parshall flume or V-notch weir; and a shelter house over a stilling well. The Stevens recorder provides a continuous record of water stage at the site. This stage is reduced to discharge in cubic feet per second and acre feet by a rating table developed for the control device which relates stage to discharge. The rating tables are modified to reflect actual site conditions by making current meter flow measurements. The measurements of instantaneous flow are made using a Price Type AA, a pygmy, or a Flowmate 2000 current meter. Information from the stream flow stations is compiled into report format quarterly and then yearly. The reports contain: daily average, maximum, and minimum flow; monthly total second foot days, acre feet, mean flow, monthly maximum and minimum • flows; and yearly total second foot days and acre feet. The reports are published and stored in an electronic medium for future reference. Yearly reports are based on a water year which starts October 1 and ends September 30. This allows moisture of a complete winter and summer cycle to be compiled in the same year. Stream flow water quality samples are collected quarterly. Prior to 1993, samples were collected at four sites. A change was made in the 1993 water year to two sites. They are Davis Gulch and Middle Fork at Lab monitoring stations. The Colony Tract streams are intermittent in nature except Davis Gulch which is perennial. Table 2 lists the sites names and sampling dates. The sampling process consists of collecting a grab sample from the stream and filling bottles supplied by the laboratory. Samples are field filtered and preserved with acid as required and then packaged in a cooler with ice for shipment to the lab. Chain of custody and sample analysis request forms are completed for all samples. When the grab sample is collected, field water quality parameters are taken for temperature, pH, conductivity, and dissolved oxygen. The stream flow is recorded along with the date, time and any remarks in the field notes. The parameters for water quality analysis have changed slightly as different contract laboratories were selected during the period of record. Table 3 shows the common parameters covered under most analyses. All water quality data is entered into a spreadsheet database for electronic storage. 2 is