A simple, self-contained canal stage recorder

Studies of surface water and shallow groundwater hydrology require intensive replicated measurements of water levels, preferably in computer-ready digital form. Commercial digital stage recorders are expensive, which prompted the design and construction of an inexpensive, automatic, digital canal stage recorder with off-the-shelf materials. This device fits into a PVC pipe used as a stilling well, making a sturdy design and very simple installation and maintenance. Step-by-step instructions on the recorder construction are presented as well as design considerations to fit a particular application. The field performance of the stage recorder was assessed in a canal in South Florida. Continuous water level readings were compared with those readings obtained at a stage recording station maintained by the South Florida Water Management District. Results obtained during the experimental period of 4.5 months showed good agreement between these two instruments (R-1:1(2) = 0.996 and y = 0. 9524x + 0.048; R-2 = 0. 998) and a measurement resolution of 0.63 cm when using an 8-bit data logger. The simple canal stage recorder could be adapted for measuring water levels in shallow wells, lakes, and tidal lagoons.