Essay on The Urbanization Of A Catchment
The urbanization of a catchment is a drastic change in land use, and has major effects on the hydrological cycle during heavy rainfall events because of its impermeable surfaces (G. E. Hollis). By recording the discharge in a catchment the data can be used to create a hydrograph. It is often useful to analyse a hydrograph because it shows how quickly rainwater moves to the stream channel (Holden J. 2012.) The aim of this study is to compare an urban and rural catchment, and to find out why they are different. To achieve this a model was used to simulate both catchments, and an accurate hydrograph for those two scenarios was made. This hydrograph will be used to explain the differences in flow, and be compared to a real world example from the Water of Leith. It is hypothesized that the runoff and discharge from the urban catchment will be greater than rural, and that the peak flow will arrive earlier for the urban catchment.
To measure the catchment of both urban and rural environment a V-section of PVC with foam glued to the surface was used. The foam represented the permeable soil in rural areas. Roles where determined in the group, with one timer, pourer and recorder. Exactly 1 litre of water was measured into a bucket with holes on the bottom that was supposed to simulate rainfall. A measuring cylinder was then placed beneath the catchment model’s outflow point so that the water poured from the bucket would be delivered into this. After 30 seconds…