Comprehensive Flow Analysis and Near-Realtime Based Streamgauging Planning at Water Control Structures

South Florida Water Management District (SFWMD) manages man-made and natural systems including the Kissimmee River, Lake Okeechobee, constructed wetlands and the Everglades. Water within this complex hydrologic system is conveyed through a network of canals and controlled by over 200 major and 2000 smaller hydraulic structures (i.e., gated culverts, gated spillways and weirs) and about 25 pumping stations. Accurate estimate of the quantity of water passing from one component of the system to the other is inevitably vital for water resources planners as well as decision makers in meeting the SFWMD's main goals including flood protection, environmental restoration and water supply. As a result of this, the SFWMD continuously monitors water levels and operation settings (gate openings and pump engine speeds) at water control structures and subsequently computes flow employing appropriate flow equations derived from governing hydraulic principles. These flow equations, however, need to be calibrated in an attempt to generate optimal values of flow equation parameters that minimize the error between computed and measured flow. For successful calibration of flow equations, however, measurements need to spread over the entire range of operation settings of the hydraulic structures and should cover all possible flow types. Planning streamgauging to minimize data redundancy and in turn cut monitoring cost entails extracting near-realtime water levels (head water and tail water) and operation conditions, identifying data gaps and determining the suitability of current conditions for taking measurements. In order to automate the flow analysis and streamgauging planning processes, a comprehensive computer tool is developed by integrating flow computation and data gap identification algorithms with flow measurement, near-realtime, and structure information databases. The developed tool including a graphical user interface has the capability to calibrate flow ratings, compute flow, summarize flow types, visualize flow parameters, depict current flow condition and identify streamgauging opportunities. The developed tool was tested on hydraulic structures including pumps, gated spillways, and gated culverts. It has subsequently applied in planning regular streamgauging as well as emergency streamgauging during the hurricane season.