The Influence of Cover on the Water Quality and Suspended Solids Under the Simulated Rainfall Condition

Highway embankments could be of equal importance when compared with the agricultural lands for the production of sediments as it carries the detached soil particles in the water which flows over land in the form of surface runoff. The downstream sedimentation from agricultural activities has always been highlighted, whereas the road related impacts are considered trivial. This paper analyzes the results, obtained from a full scale test with rainfall simulation on the fully grass covered surface (Plot-I) and the exposed soil surface (Plot-II) for the inevitable issue of water quality and turbidity affected by the soil erosion. The study was conducted on a filled embankment having slope angle of 30° which observed a marginal difference under the rainfall intensity of 40 mm/hour for both the plots. The results obtained recommend fully grass covered surface to mitigate this problem to an extent. The maximum turbidity and suspended particle values for Plot-I were found to be 75 (NTU) and 11.3 (mg/L) whereas, for Plot-II the values were found to be 1631.5 (NTU) and 52.3 (mg/L) respectively.