USGS Scientific Investigations Report 2010–5065Channel Change and Bed-Material Transport in the Lower Chetco River, Oregon

Table 6. Summary of calculated transport rates for the Chetco River, Oregon.

[Diameter: d₁₆, grain size diameter in millimeters, where 16 percent of the sample is finer by volume; d₅₀, grain size diameter in millimeters, where 50 percent of the sample is finer by volume; d₈₄, grain size diameter in millimeters, where 84 percent of the sample is finer by volume; Percent <2 mm: percent less than 2 millimeters. Abbreviations: Rkm, river kilometer; FPkm, flood-plain kilometer; kg/s, kilogram per second; m³/s, cubic meter per second; m³/yr, cubic meter per year; <, less than]

Cross section location		Diameter (mm)			Percent <2 mm	Distance to surface sample site (m)	Equation	¹ Low flow cut off (m³/s)	Energy slope (percent)	Transport rate (kg/s)	Energy slope (percent)	Transport rate (kg/s)	Energy slope (percent)	Transport rate (kg/s)	Energy slope (percent)	Transport rate (kg/s)	Energy slope (percent)	Transport rate (kg/s)	² Mean annual transport, 1970–2008 (m³/yr)
Rkm	FPkm	d₁₆	d₅₀	d₈₄	Percent <2 mm	Distance to surface sample site (m)	Equation	¹ Low flow cut off (m³/s)	50 m³/s		100 m³/s		500 m³/s		1,000 m³/s		2,000 m³/s		² Mean annual transport, 1970–2008 (m³/yr)
16.9	15.3	12.76	38.64	82.80	3.7	250	Parker	150	0.333	0.246	0.245	0.293	0.214	60	0.229	305	0.217	568	51,100
							Wilcock- Crowe	50		1.414		1.883		89		306		509	73,900
16.5	14.9	11.86	28.87	57.42	0.0	250	Parker	100	0.035	0.000	0.060	1.364	0.180	98	0.180	270	0.170	793	103,200
							Wilcock- Crowe	100		0.000		0.660		47		113		324	54,300
14.6	13.3	18.64	37.15	63.07	1.0	270	Parker	100	0.119	0.001	0.161	10.436	0.211	38	0.183	167	0.161	600	79,100
							Wilcock- Crowe	100		0.009		5.630		21		84		278	43,600
12.6	11.5	11.00	36.33	72.13	3.5	180	Parker	230	0.053	0.000	0.066	0.000	0.179	118	0.243	485	0.248	789	83,000
							Wilcock- Crowe	170		0.000		0.053		136		444		663	91,100
9.4	8.5	21.78	53.26	89.40	1.0	850	Parker	450	0.036	0.000	0.059	0.000	0.143	4	0.171	30	0.119	3	5,700
							Wilcock- Crowe	425		0.000		0.000		4		23		5	4,100
6.0	5.3	10.40	19.75	37.96	3.0	20	Parker	110	0.152	0.004	0.155	0.116	0.086	10	0.083	78	0.084	326	9,600
							Wilcock- Crowe	110		0.108		0.673		11		56		189	10,100
3.1	2.6	2.50	11.93	30.10	12.0	240	Parker	230	0.027	0.000	0.040	0.000	0.049	2	0.051	38	0.063	310	3,900
							Wilcock- Crowe	100		0.101		0.548		16		99		402	15,100

¹ Low flow cut off determined from Q-Q_s relations based on unit flow data.

² Annual transport 1970–2008 calculated from regression between daily transport (based on unit flow values) and daily mean discharge.