An Analysis of the Relation Between Values of D50 and Discharge for Several Rivers in Endau River Catchment Area, Johor, Malaysia.

This paper examines the relationship between the values of median grain size (D50) and average discharge for several rivers in Endau River catchment area, Johor, Malaysia. Madek, Dengar and Mengkibol rivers were surveyed at these stage and the result shows that there is a weak relation between median grain size (D50) and average discharge. The flow rate for Dengar river upper station was 0.87 m3/s and the D50 were 4.5 mm, where the flow rate for the lower station for Dengar river was 0.23 m3/s and the D50 were 2.4 mm. The result obtained from Mengkibol river were different where the flow rate for upper and lower stations was very high when compared to Dengar river which is 2.91 m3/s and 3.11 m3/s respectively but the values of D50 was similar which was 3.0 mm for upper station and 2.4 mm for lower station. Result obtained for Madek river was huge different, where the flow rate for upper station was 1.23 m3/s and the D50 were 4.5 mm, whereas the flow rate for the lower station was similar which is 1.26 m3/s but the D50 value was 41.5 mm