The design of monitoring programs often serves as one of the major sources of error or uncertainty in water quality data. Properly designed programs should minimize uncertainty or at least provide a means by which variability can be partitioned into recognizable components. While the design of sampling programs has received recent attention, commonly employed strategies for limnological sampling of lakes may not be completely appropriate for many reservoirs. Based on NES data, reservoirs are generally larger, deeper, and morphologically more complex than natural lakes. Reservoirs also receive a majority of their inflow from a single tributary located a considerable distance from the point of outflow. The result is the establishment of marked physical, biological, and chemical gradients from headwater to dam. The existence of horizontal as well as vertical gradients, and their importance in water quality sampling design were the subject of intensive transect sampling efforts at DeGray Lake, a U.S. Army Corps of Engineers reservoir in southern Arkansas. Data collected were used to partition Variance, identify areas of similarity, and demonstrate how an equitable sampling program might be designed.

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The Texas Parks and Wildlife Department (TPWD) conducted surveys to determine the accuracy of trip durations reported by marine sport‐boat fishermen. The surveys were conducted at boat ramps on 21 d during May‐August 1982. The fishermen's reported trip duration (nearest 0.5 h) was compared to TPWD's observed trip duration (nearest 0.1 h). No significant differences were found between the reported and observed trip durations by sport‐boat fishermen. Eighty‐six percent of all differences between reported and observed trip durations were within ± 1.0 h of zero, and 68% of those differences were within the precision desired (nearest 0.5 h). Therefore, the mean trip duration reported by sport‐boat fishermen during 1‐d fishing trips is an empirically unbiased estimate of actual mean trip duration. The accuracy of trip duration reported by sport boaters was not influenced by the actual trip length.