This project was carried out by my team and i last week but i just finished compiling the report now. We have just 3 ladies in my class and we were made group leaders for different erosion sites. The project was carried out to test our knowledwge on the different types of erosion,causes and control.

DESCRIPTION OF SITE WITH DATE

The project was carried out on the 25th of June,2018 at an erosion site located beside Abattoir shop ,along Botanical garden,University of Ibadan,Oyo state.

EROSION TYPE

The type of erosion witnessed is ephemeral GULLY EROSION. It is ephemeral because it is not too large to be smoothened by regular tillage or crossed by machinery. The channel is shallow and can be corrected but if not worked upon in close time, the erosion is very prone to becoming a permanent gully erosion. The erosion channel is slightly above 0.3m width and above 0.3m depth. The erosion is more severe at the end. with greater depth due to the velocity as it which the water flows.

FACTORS THAT CAUSED THE EROSION

1. POOR DRAINAGE SYSTEM:-
   
   The drainage system beside the erosion site was not properly constructed. It is not wide enough to contain the water flowing through it,the positioning is wrong and the pipe that is supposed to channel the water downstream is blocked.

2. RUN OFF:-
   I
   The surface flow is the main cause of erosion in the site. The land just before the erosion site is tiled so water is not absorbed as there is absence of soil. All the water flowing down from the street meets the bad drainage then transports itself to the erosion site. The water gets absorbed by the soil, fills up the soil pores and surface depressions then accumulates on the soil surface at a given depth.

3. SLOPE OF THE LAND:- The land is very sloppy,the area were the erosion is occurring is lower than the other end of the road. Water flows from the higher level ground to the lower level groud and settles there, causing water log which further leads to erosion.

4. SHEAR STRESS:- From our observation, the shear stress of runoff is greater than the critical shear of the soil. The shear stress of flow is responsible for continued detachment of the channel bed and sides and transports eroded materials along the well defined ephemeral channels.

CONTROL MEASURES

1. PROPER DRAINAGE:- The drainage at the location needs to be corrected,the drainage has to be widened to contain the runoff and the blockage obstructing the runoff from flowing through the right channel that leads to the downstream has to be fixed.

2. SAND FILLING:- The erosion although deep can still be sand filled and compacted after the drainage has been fixed.

RECOMMENDATION AND CONCLUSION

We recommend that the site of erosion should not be ignored, if action is not taking as soon as possible, the erosion will become more severe and lead to a permanent gully erosion that will affect the road where passersby and vehicle pass to get to their destination.

GROUP PHOTOGRAPHY BY TEAM MEMBERS

Thanks for reading. Brought to you by the versatile student Engineer