Standard Guide for Collection of Water Temperature, Dissolved-Oxygen Concentrations, Specific Electrical Conductance, and pH Data from Open Channels

5.1 This guide describes stabilization criteria for recording field measurements of Temperature, DO, SC, and pH.

5.2 This guide describes the procedures used to calibrate and check meters to be used in the field to records these measurements and the procedures to be use in the field to obtain these data.

5.3 This guide describes quality assurance procedures to be followed when obtaining cross-sectional means of temperature, dissolved oxygen, specific electrical conductance, and pH of water flowing in open channels.

5.4 Field measurement must accurately represent the water flowing in the open channel being measured. Methods need to be used that will result in an accurate representation of the mean of the parameter of interest. Procedures must be used that will take into consideration the variation in the parameter across the sections and with depth.

5.5 Temperature and DO must be measured directly in the water in the open channel. SC and pH are often measured in situ, but also may be measured in a subsample of a composite sample collected using discharge-weighted methods.