Useful Tools in Hydrology

Flash floods are often described on the news as having come without warning. However, we have instrumentation such as rain and stream gauges that assist in foreseeing such events. Floods can be caused by immense amounts of rainfall from powerful storms or by a sudden increase in the water levels in rivers and streams (Hapuarachchi et al. 2771). The method to correctly predict floods is to have accurate ways of measuring the rate at which the rain is falling and to monitor the water level of moving water. Together, rain gauges and stream gauges can assist in predicting flash floods and other environmental occurrences.

A pluviometer, more commonly known as a rain gauge, is a device that measures the amount of precipitation or rain that is accumulated over a set period of time (Onacak and Yurur 552). They often function by using a tipping bucket method in which a bucket of known volume is dumped over when it reaches a predetermined volume (552). The number of times the bucket tips in a certain amount of time will give you a rate of rainfall. The disadvantage to this method is that the time it takes the bucket to tip over is several seconds and in that time water goes uncollected (Onacak & Yurur 552). This can play a more significant role when the precipitation rate is high.

Stream gauges can also provide people with important information such as flood plain mapping, reservoir development, bridge design, water quality, and climate change information (Juracek and Fitzpatrick 329). All of these measurements and applications of stream gauges are affected by precipitation frequency and rate because the rain affects stream water levels. Stream gauges can provide a large variety of information depending on the gauging station including water levels, flow rate, and water temperature (Juracek and Fitzpatrick 329). The information provided by both rain and stream gauges can help in predicting flash floods by determining the rate of precipitation and how quickly the streams are flowing. The flow rate of the stream can affect the composition of channel bar deposits by altering the sediment deposition in certain areas in a stream system.

Channel bar deposits also play a role in the evolution of streams and rivers. Evaluation of channel bar deposits can assist in determining aquatic habitat sustainability, appropriate infrastructure, and management of water reservoirs (Heitmuller and Hudson 246). Studying channel bar deposits allows researchers to identify streams that are experiencing erosion, sediment transport, or sediment deposition (247). All of these factors can affect surrounding landmarks or infrastructure. Significant erosion or sediment transport can lead to changes in the stream or loss of a stream. Channel bar deposits can show the deposition of sediment from upstream lakes or rivers (Heitmuller and Hudson 248) Channel bar deposit composition can also be indicative of changes that are happening upstream in river systems. This can also predict the type of aquatic ecosystem that does or could inhabit this portion of a stream and ultimately help predict environmental patterns.

All of the information that can be obtained using rain and stream gauges, combined with channel bar deposit data, can assist in accessing the status of bodies of water and in predicting issues with watershed planning. Although flash floods prediction seems the most pertinent, the use of these other tools will allow researchers to determine trends in channel bar deposits, precipitation rates and stream data.

Works Cited

Hapuarachchi, H. A. P., Q. J. Wang, and T. C. Pagano. "A Review Of Advances In Flash Flood Forecasting." Hydrological Processes 25.18 (2011): 2771-2784.

Heitmuller, Franklin T., and Paul F. Hudson. "Downstream Trends In Sediment Size And Composition Of Channel-bed, Bar, And Bank Deposits Related To Hydrologic And Lithologic Controls In The Llano River Watershed, Central Texas, USA." Geomorphology 112.3-4 (2009): 246-260. (Heitmuller & Hudson, 2009)

Juracek, Kyle E., and Faith A. Fitzpatrick. "Geomorphic Applications Of Stream-gage Information."River Research and Applications 25.3 (2009): 329-347.

Onacak, Turkay, and Mehmet Tekin Yurur. "A New High Precision Pluviometer System."Instrumentation Science & Technology 35.5 (2007): 551-561.