End of Wet Season Stream Flow Measurements, Roper River, May 2014
Kerle, Errol; Waugh, Peter; Northern Territory. Department of Land Resource Management
E-Publications; E-Books; PublicationNT; Aug-14
Early dry season snapshot measurements were taken on the Roper River to establish water quality and quantity conditions at commencement of baseflow conditions. The snapshot measurements are used to: 1. Refine and calibrate the hydrological model used to assess resource availability and allocations. 2. Better define aquifer recharge/discharge zones along the river, and 3. Provide a dataset of comparable flow and water quality measurements at identical periods in the annual water cycle.
Made available via the Publications (Legal Deposit) Act 2004 (NT)
Summary -- Aim -- Introduction -- Observations -- Discussion -- Conclusion -- Recommendations -- References
End of Wet Season Stream Flow Measurement
Northern Territory Government
24 pages : illustrations, colour maps ; 30 cm.
Attribution International 4.0 (CC BY 4.0)
Northern Territory Government
19 Type Conditions Influences Description Gauge Plates Unstable gauge posts Unstable gauge posts create inaccuracies in the gauge plate heights. Unreadable gauge plates Gauge plates that are in a bad condition is difficult to read and create inaccuracies in the readings Gauge Plate Numbers Missing numbers create confusion and can create mistakes of up to 1m in gauge plate readings. Surveys In correct surveys and adjustments on gauge plates causes error in gauge plate readings. Ground water Production Boreholes Size of Well Insufficient space to perform water level measurements with existing equipment Pumping Pumping operations influences the water level measurements Casing Collar Unstable casing Unstable casing causes errors in the water level measurement Level Indicators Equipment condition Instruments with faded increments can cause errors in measurements. Increments Course increments on tape measure will lead to different interpolation of values Stream Flow Factors influencing accuracy of discharge measurements are categorised under environmental and system influences. System influences are created by the type of instrumentation used and can be minimised if standards are followed. Environmental influences result from site conditions and actions by the operator and generally have a much greater impact on measurement accuracy. Environmental factors that have an influence on the accuracy are the following: W: Wind: The wind causes the water level to osculate which has a large effect on the flow if the wind direction is parallel with the flow direction. LP: Large pools: Reduce velocity drastically WG: Water grass: Influences the flow measurements, very high inaccuracies with depth and velocity measurements. A: Algae growth: Algae that floats in the water influence the signal strength of the ADCP. The Hydraulic (H) requirements of a monitoring section are essential for accurate discharge measurements. As far as possible, the monitoring site needs to comply with the following hydraulic requirements during the gauging section selection process: Uniform cross section Flow in the stream should be confined to a single well-defined channel with stable banks. Bends upstream of site must be avoided if possible