Bank‐full discharge of rivers

Williams, Garnett P.

doi:10.1029/wr014i006p01141

Cited by 628 publications

(497 citation statements)

References 23 publications

Supporting

Mentioning

462

Contrasting

Unclassified

Order By: Relevance

“…The channelforming flow is often taken to be approximately the bank-full flow, i.e., the largest flow that can be conveyed by the channel-one that just fills the channel without overtopping the banks (Leopold et al (1964)). The bank-full flow is generally of the same order as the mean annual flood, although the return period may be appreciably different in individual streams (Williams 1978).…”

Section: Channel Forming Flowmentioning

confidence: 93%

Stream channels are narrower in pasture than in forest

Davies‐Colley

1997

New Zealand Journal of Marine and Freshwater Research

154

117

View full text Add to dashboard Cite

In the Hakarimata Range, west of Hamilton, New Zealand, second-order streams appear to be wider in native than in pasture catchments, whereas streams in pine plantations (18 years old) appear to be suffering active stream-bank erosion. A working hypothesis to explain these observations was that pasture vegetation replacing original forest encroaches on the stream channel, causing it to become narrower. To test the hypothesis, channel widths were measured up stream and down stream of "transitions" from native forest to pasture in 20 streams of different size in marginal ranges of the Waikato Basin. Small streams (catchment area <1 km 2 , width in forest <2 m) were found to be half the width in pasture reaches as in forest. The degree of channel narrowing decreased as stream size increased and was minimal in large streams (catchment area >30 km 2 , width in forest >10 m). This narrowing of stream channels implies that native forest clearance in New Zealand has reduced stream channel habitat. A concern regarding riparian planting for stream restoration is that sediment stored in pasture stream banks could be mobilised if grasses are extinguished by shading, resulting in turbid streamwater and sedimentation of fines in the channel.

show abstract

Section: Channel Forming Flowmentioning

confidence: 93%

Stream channels are narrower in pasture than in forest

Davies‐Colley

1997

New Zealand Journal of Marine and Freshwater Research

154

117

View full text Add to dashboard Cite

show abstract

“…Considerable progress has been made in the USA in estimation of discharge from channel geometry for specific regions and is summarized by Wahl (1984). In the central USA, Williams (1978) established relationships between bankfull discharge and channel dimensions for 36 gauging stations. Outside the USA, success has been reported for New Zealand (Mosley, 1979), northwest Italy (Caroni, 1982), Great Britain, Java, Burundi, Ghana and Tanzania (Wharton et al, 1989(Wharton et al, , 1995(Wharton et al, , 1999.…”

Section: Flood Estimation From River Channel Dimensionmentioning

confidence: 99%

Estimation of peak streamflows through channel geometry / Estimation de pics de débit fluviatiles à l'aide de la géométrie des cours d'eau

Bhatt

Tiwari

2008

Hydrological Sciences Journal

View full text Add to dashboard Cite

“…Bankfull discharge is considered to be at or close to the channel-forming discharge and as a particularly important hydrological and geomorphic parameter (Wolman and Leopold, 1957;Williams, 1978;Osterkamp, 2004;Wu et al, 2008). Fig.…”

Section: Bankfull Channel-form Adjustmentmentioning

confidence: 99%

Channel adjustments in response to the operation of large dams: The upper reach of the lower Yellow River

et al. 2012

View full text Add to dashboard Cite

The Yellow River in China carries an extremely large sediment load. River channel-form and lateral shifting in a dynamic, partly meandering and partly braided reach of the lower Yellow River, have been significantly influenced by construction of Sanmenxia Dam in 1960, Liujiaxia Dam in 1968, Longyangxia Dam in 1985 and Xiaolangdi Dam in 1997 Using observations from Huayuankou Station, 128 km downstream of Xiaolangdi Dam, this study examines changes in the river before and after construction of the dams. The temporal changes in the mean annual flow discharge and mean annual suspended sediment concentration have been strongly influenced by operation of theses dams. Observations of sediment transport coefficient (ratio of sediment concentration to flow discharge), at-a-station hydraulic geometry and bankfull channel form observed from 1951 to 2006 have shown that, although variations in flow and sediment load correspond to different periods of dam operation, changes in channel form are not entirely synchronous with these. The channel has been subject to substantial deposition due to the flushing of sediment from Sanmenxia Dam, resulting in a marked reduction in bankfull cross-sectional area. Flows below bankfull had a greater impact on channel form than higher flows because of very high sediment load. At-a-station hydraulic geometry shows that the variation of channel cross-sectional area below bankfull in this wide and relatively shallow system largely depends on changes in width. Such at-a-station changes are significantly influenced by (1) events below bankfull and (2) overbank floods. Bankfull depth is the main component of channel adjustment in that depth adjusts synchronously with channel area. The channel adjusts its size by relatively uniform changes in depth and width since 1981. Channel morphology is not the product of single channelforming flow frequency. It is determined by the combination of relatively low flows that play an important role in fine sediment transport and bed configuration as with relatively high flows that are effective at modifying the channel's morphology. The sediment transport coefficient is a useful index for efficiently guiding the operation of the dams in a way that would minimize channel changes downstream. Sedimentation over the nearly 60 years of study period caused the lower Yellow River to aggrade progressively, the only significant exception being the two years following completion of Sanmenxia Dam.

show abstract

Bank‐full discharge of rivers

Cited by 628 publications

References 23 publications

Stream channels are narrower in pasture than in forest

Stream channels are narrower in pasture than in forest

Estimation of peak streamflows through channel geometry / Estimation de pics de débit fluviatiles à l'aide de la géométrie des cours d'eau

Channel adjustments in response to the operation of large dams: The upper reach of the lower Yellow River

Contact Info

Product

Resources

About