1 River Darent: Data
Three examples of typical data collected by students are given below:
Site Number: One Stream width: 8.4 metres Stream depth (recorded every metre): 0.18m 0.23m 0.21m 0.20m 0.23m 0.15m 0.16m 0.17m blank blank blank blank Velocity (recorded a quarter, half-way and three-quarters of the way across the stream): 0.98m/sec 0.83m/sec 0.67m/sec Bedload size and angularity (sample of six pebbles): with Powers chart underneath 40mm 30mm 20mm 25mm 15mm 32mm 3 5 3 3 4 4 Comments: Natural banks with vegetation, no obstructions in the stream, stream bed very stony all the way across with little evidence of mud or sand. Site Number: Two Stream width: 10.2 metres Stream depth (recorded every metre): 0.25m 0.22m 0.17m 0.20m 0.17m 0.13m 0.09m 0.05m 0.10m 0.32m blank blank Velocity (recorded a quarter, half-way and three-quarters of the way across the stream): 0.70m/sec 0.54m/sec 0.60m/sec Bedload size and angularity (sample of six pebbles): with Powers chart underneath 20mm 35mm 40mm 45mm 30mm 26mm 5 3 4 2 5 2 Comments:Some branches fallen into the stream, natural banks with vegetation, just after a meander, bedload of different sizes.
LMcG 29 July 2008 2 Site Number: Three Stream width: 13.6 metres Stream depth (recorded every metre): 0.31m 0.29m 0.28m 0.23m 0.18m 0.20m 0.18m 0.17m 0.16m 0.22m 0.23m 0.19m Velocity (recorded a quarter, half-way and three-quarters of the way across the stream): 0.44m/sec 0.42m/sec 0.27m/sec Bedload size and angularity (sample of six pebbles): 90mm 45mm 40mm 42mm 45mm 36mm 6 3 4 4 4 4 Comments:Artificial banks with some vegetation, no obstructions in the stream, stream bed full of large stones and some pieces of brick.
LMcG 29 July 2008 3 River Meon
Mean Distance Mean Slope Mean Mean Pebble Site from Cross Mean Velocity Mean Angle Sample Site Width Discharge Pebble Long Number Source Section Depth (m) (m/s) (raw (m) (m3) Roundness Axis (km) Area (m2) degrees) (mm) East Meon 1 1.9 0.29 3.25 0.09076786 0.18 0.05 2.75 40.5 3.5 Westbury 2 4.9 0.65 3.75 0.17375 0.2333333 0.15 2.95 82.45 2.5 Exton 3 11.5 2.48 8.25 0.30018301 0.5783333 1.43 3.45 81.375 3.466667 Droxford 4 14.5 3.68 13.25 0.27800398 0.335 1.23 3.65 47.125 2.5 Soberton 5 16.5 0.93 6 0.155 1.135 1.06 3.575 56.125 1.833333 Mislingford 6 19.4 1.77 5 0.35442857 1.06 1.88 3.3 43.55 2.333333 Funtley A (After Split/Sluice) 7 26.4 1.15 5 0.22909091 0.5166667 0.59 3.25 32.75 2 Funtley B (Canalised) 8 26.5 1.37 4.5 0.305 0.3666667 0.50 3.4 37.65 1.666667 Bellfield 9 30.0 2.87 8 0.35823529 0.0116667 0.03 3.5 40.125 0.75
LMcG 29 July 2008 4 And there is detail from 3 of these: East Meon Transect s i x t s f s A e
) e s L g s
n . / ) e n ) l d o m o g m m n m ( ( o N L n (
u r
f y h o A
e e k t l t i e n n R p b e c
c o a e b p t o e n l l B e o D S l a e b t P S b V ) s i e m D P m ( Velocity 1 0.16 0 0.08 1 60 3 Slope 1 3 Velocity 2 0.22 0.5 0.09 2 30 4 Slope 2 2 Velocity 3 0.1 1 0.1 3 40 3 Slope 3 3 Av. Average 0.16 1.5 0.1 4 75 2 2.7 Slope 2 0.1 5 45 3 2.5 0.1 6 50 4 3 0.09 7 70 3 Average 0.0943 8 90 3 9 60 2 10 40 3 11 55 3 12 40 3 13 35 2 14 30 3 15 100 2 16 80 2 17 80 2 18 50 2 19 40 3 20 30 3 Av 55 2.75
LMcG 29 July 2008 5 Soberton Transect
LMcG 29 July 2008 6 t s f s s i e ) x e s L s
n A . / e )
) l d o m g g m m n m ) ( o ( N n n (
u r
f o m y h o A
e k t t L i e n
n m R p e c
( c o e a e p l t o e n l l B o b D S l a e b t b S b V s e i e P D P Velocity 1.36 0 0.03 1 90 3 Slope 1 2 1 Velocity 1.36 0.5 0.12 2 30 5 Slope 2 -2 2 Velocity 1.36 1 0.15 3 40 4 Slope 3 1 3 Av. Average 1.36 1.5 0.18 4 35 4 0.33 Slope 2 0.19 5 50 4 2.5 0.2 6 70 5 3 0.18 7 30 5 3.5 0.17 8 20 3 4 0.12 9 40 3 4.5 0.14 10 80 2 5 0.17 11 70 4 5.5 0.15 12 70 3 6 0.18 13 50 3 Average 0.152308 14 70 4 15 110 2 16 90 4 17 20 4 18 10 5 19 15 4 20 30 2 Av 51 3.65
LMcG 29 July 2008 7
Bellfield Transect t s f s s i e ) x e s L s
n A . / ) e
) l d o m g g m m n m ) ( o ( N n n (
u r
f o m y h o A
e k t t L i e n
n m R p e c
( c o e a e p t l o e n l l B o b D S l a e b t b S b V s e i e P D P Velocity 0.01 0 0.07 1 50 3 Slope 1 0 1 Velocity 0.02 0.5 0.18 2 80 3 Slope 2 0 2 Velocity 0.01 1 0.23 3 60 3 Slope 3 1 3 Av. Average 0.013333 1.5 0.29 4 50 2 0.333333 Slope 2 0.33 5 40 2 2.5 0.37 6 60 3 3 0.39 7 60 3 3.5 0.41 8 70 3 4 0.44 9 40 4 4.5 0.46 10 40 3 5 0.47 11 50 5 5.5 0.45 12 50 3 6 0.46 13 100 3 6.5 0.45 14 50 3 7 0.48 15 50 4 7.5 0.49 16 70 3 8 0.12 17 50 4 Average 0.358235 18 40 3 19 40 6 20 80 3 Av 56.5 3.3
LMcG 29 July 2008