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I I I I I I I I I I I I I I I I I I I OnJlJ18 Stream Gauges Stream gauge design and installation have posed significant problems for the other Colorado flash flood detection systems. Traditional methods of gauging with stilling wells at flumes or weirs requires construction that is typically too costly or environmentally obtrusive. This has fostered attempts to develop methods of gauging at natural cross sections with suitable accuracy for flash flood detection purposes. These efforts have met with mixed success, and a number of pitfalls remain. We believe our experience in this area would be useful to the Pikes Peak Region. Visibility and camouflage, damping of wave action, and resistance to periodic drying and freezing all need to be addressed in the selected equipment. since the siting of stream gauges is so constrained, it is usually necessary to minimize visibility, either to reduce vandalism or to satisfy private landowner concerns. Pressure transducer (PT) sensors seem to offer a viable solution, since the instrument is small and can be installed directly in the stream channel. Concealed housings for the RTU have been used by SCC to complete camouflaged installations elsewhere. Some PT's are vulnerable to severe damage by the extreme pressures which may occur if ice forms in the instrument. The vibrating wire PT is more immune to ice damage, and may offer some significant advantages in this application. It is readily compatible with the equipment specified in the event/polled section of this proposal. The damping of wave action can be best accomplished by using an RTU with sufficient programmable intelligence to take frequent readings, average them, and detect significant changes and trends from the data. Again, the equipment configuration for the event/polled alternative would provide this capability without sacrificing resolution or response time. Weather Ra\iar As a service which is optional to this proposal, SCC is willing and qualified to perform integration and installation of weather radar equipment at the central monitoring site. National Weather Service radar from Limon, Colorado would be displayed in real time via telephone line on a Kavouras Radac 1000 or Radac 2 receiver unit. The latter promises to be a significant new offering scheduled for release in the second quarter of 1987; we recommend that the Region delay any purchase commitment until this new release can be evaluated. New features include the ability to integrate high resolution satellite imagery, and a color printer output port. This feature could ultimately allow a printed output which combines radar imagery with "ground truth" from the flash flood detection network. sce - pikes Peak Early Flood warning Proposal 7