Gully Erosion Control Studies (A Case Study Of Amucha Ebeise, Njaba Local Government Area, Imo State)

ABSTRACT

Gully erosion has greatly contributed a lot of damages to the study area (Amucha Ebeise). This study was conducted using soil sample collected from the area under study and as well, using the rainfall data of Njaba from 1990-2010. Two soil samples labeled A and B were collected at a depth of 1m and 1.2m (upper and lower region of the gully) at the study area. Laboratory test like moisture content, sieve analysis, liquid limit, plastic limit and specific gravity experiment were carried out on the soil to determine it’s Engineering properties. The soil was classified using AASHTO as A-2-4(o) with liquid limit of 19.93 and plastic index of 7.21.

The moisture content of 9.00 and specific gravity of 2.54 were also determined. The summary of this result indicated that the soil is good and also has good drainage properties. Also, the rainfall intensity from the 10years return is 354.6mm which is too high and is the major cause of the erosion.

 CHAPTER ONE

1.0  INTRODUCTION

1.1  BACK GROUND OF THE STUDY

The formation of gullies   has become one of the greatest environment disasters facing many towns and villages in South Eastern Nigeria. This region is fast becoming hazardous for human habitation.

Hundreds of people are directly affected every year within towns and villages and have to be re-located yet the rate of increase in gully erosion has continued unabated with no suitable solution.

The economic cost of gully erosion control in south eastern Nigeria is devastating. Gully erosions lead to great losses of land every year. Large sections of land have been destroyed in recent years in Umuzikabumu. Of Amucha Ebeise town in Njaba Local Government Area. The gully erosion   has assumed an alarming dimension, claiming farm lands of the people. They no longer feel safe, as they watch their earth roads being engulfed by gully erosion as shown in the appendix. The farmers in the area find it difficult to evacuate their farm produce.

Every rainy season, usually lasting from April to October, new gullies are created and old ones are deepened and also widend. The top soils required for Agricultural purpose are also washed away as sheet, rill, or gully erosion is collected into water causes, bringing about stream pollution and siltation.

In most cases, the cause of gully erosion are associated to the natural slope of the area and the strength of the bond between soil particles.  Other natural factors are climate, topography, soil type, vegetation (land use). Human factors such as inadequate drainage and poor construction contribute to the formation of gully erosion. It is now clear that erosion does not only bring about long term detrimental change in the soil such as reduction of soil depth, but also has an immediate influence on soil fertility, productivity and farming cost.

 1.2  STATEMANT OF PROBLEM

Observations and findings from the study area proved that the area is facing the menace of gully erosion. The Amucha Ebeise gully started during the earlier seventies as rill and later developed to gully erosion due to the ignorance of the people.  The uncontrolled felling of trees and over grazing in the area has contributed a lot to the problem of gully erosion. It all started from a farm road, developed occupying a large hectares of farm land of the people.

1.3  OBJECTIVES OF THE STUDY

1. i) The objective of this project is to study, know the cause and solution to gully erosion at Amucha in Njaba Local Government Area of Imo State.
2. ii) To know the stages of erosion that leads to gully erosion.
3. iii)   To protect the two most valuable natural resources (water and soil).
4. iv) Preventing the reoccurrence of the unfavourable consequences which their deterioration (water and soil) could have for various branches of the natural economy, namely for agriculture, water management and for the human environment.

1.4  SCOPE OF THE PROJECT

The scope of this project is to analyse and determine the causes of gully erosion in Amucha and to find out the possible remedies to over come the erosion problem in this area.

1.5  JUSTIFICATION OF THE PROJECT

The justifications of this project are;

1. i) To proffer solution to the source of erosion in that area thereby minimizing growth of gullies.
2. ii) To serve as a reference to all who will handle future projects on erosion hazards and drainage designs.

iii)   To prepare a work that will serve as an academic tool to help students and Engineers to handle related projects with confidence.

1.6  DEFINITION OF TERMS

EROSION: This is the process by which soil materials are removed from the surface and transported to another location either by rain, wind or any other agent.

TOP SOIL:  This is the upper, outmost layer of soil usually the top 2 inches (5.1cm) to 8 inches (20cm). it has the highest concentration of organic matter and microorganisms and is where most of the Earth’s  biological  soil activity occurs.

GULLY EROSION: Gully erosion results from water moving in rills, which concentrate to form larger channels. When rill erosion can no longer be repaired by merely tilling, it is defined as gully erosion.

RUNOFF: This is the water flow that occurs when the soil is infiltrated to full capacity and excess water from rain, melt water, or other sources flows over the land.

Pages:  76

Category: Project

Format:  Word & PDF               

Chapters: 1-5                                          

Source: Imsuinfo

Material contains Table of Content, Abstract and References.