A consequence of stirring sea bottoms within construction sites is that suspended particles are being released. Pollutants such as heavy metals are often bonded to suspended particles which can spread over long distances. Analyzing the levels of particles in the water can either be made in a laboratory, or by measuring turbidity. Turbidity is a measure of the water’s ability to diffuse light and is used to determine the content of suspended material. This thesis is made in collaboration with AFRY who is preforming water sampling during a construction of a new quay area in Kallholmsfjärden, Skellefteå. The purpose of this study has been to investigate if, and how, suspended substances are being spread during water-based constructions that causes stirring of the sea bottom. The study was carried out by analyzing data sampled from Kallholmsfjärden. In summary, the result indicate that water-based constructions may result in suspended substances being spread into the water. Suspended material is correlating with turbidity, which means that turbidity can be used as an indicator for suspended materials. The kind of operation preformed during construction, affects the turbidity and dredging leads to higher particle scattering than padding. The result underlines the importance of taking preventive measures that reduce particle scattering, and one way of doing that is by using silt curtains. According to the result, silt curtains fulfill its purpose by preventing particle scattering. Finally, there is no difference in suspended material between dissimilar depths. The result of this theses is relevant when planning similar projects.

<p>The project was conducted on a small-scale catchment at Goedertrou in the Riebeek- Kasteel district. The focus of this study was to address some of the hydrological processes active in the research catchment, namely infiltration, run-off and sediment mobilisation on different soil types. It was done to investigate the origin of Berg River pollutants. To answer the overall question about what influence the natural salt load of the Berg River, a number of subprojects have been identified, one of which is to understand the hydrological processes in the soil mantle and vadose zone. Hence, the study aimed to answer the research questions mentioned and discussed in section 1.3 of Chapter 1. Considering the results, it could be suggested that decayed root systems from the rows of plants, soil cracks, small channels and openings created by small animals, as well as slope orientation and, therefore, soil composition, all played a major role in influencing the ability of the soil to absorb the simulated rainfall. In this study, the factors that influenced run-off are micro topography, soil moisture, root system, animal activities in soil profile, soil crack dimensions and the hydraulic conductivity. The main factors that played a major role to influence sediments mobilisation are strongly believed to be the micro topography within the ring, slope gradient and length, vegetation cover and rainfall-simulation intensity. After using different techniques, the results show that farmers must be aware that with storm rainfall, particles smaller than 65 &mu / m are subject to mobilisation. It is important to let land-users know that they need proper and appropriate methods for land-use.</p>

<p>The project was conducted on a small-scale catchment at Goedertrou in the Riebeek- Kasteel district. The focus of this study was to address some of the hydrological processes active in the research catchment, namely infiltration, run-off and sediment mobilisation on different soil types. It was done to investigate the origin of Berg River pollutants. To answer the overall question about what influence the natural salt load of the Berg River, a number of subprojects have been identified, one of which is to understand the hydrological processes in the soil mantle and vadose zone. Hence, the study aimed to answer the research questions mentioned and discussed in section 1.3 of Chapter 1. Considering the results, it could be suggested that decayed root systems from the rows of plants, soil cracks, small channels and openings created by small animals, as well as slope orientation and, therefore, soil composition, all played a major role in influencing the ability of the soil to absorb the simulated rainfall. In this study, the factors that influenced run-off are micro topography, soil moisture, root system, animal activities in soil profile, soil crack dimensions and the hydraulic conductivity. The main factors that played a major role to influence sediments mobilisation are strongly believed to be the micro topography within the ring, slope gradient and length, vegetation cover and rainfall-simulation intensity. After using different techniques, the results show that farmers must be aware that with storm rainfall, particles smaller than 65 &mu / m are subject to mobilisation. It is important to let land-users know that they need proper and appropriate methods for land-use.</p>

Magister Scientiae - MSc / The project was conducted on a small-scale catchment at Goedertrou in the Riebeek- Kasteel district. The focus of this study was to address some of the hydrological processes active in the research catchment, namely infiltration, run-off and sediment mobilisation on different soil types. It was done to investigate the origin of Berg River pollutants. To answer the overall question about what influence the natural salt load of the Berg River, a number of subprojects have been identified, one of which is to understand the hydrological processes in the soil mantle and vadose zone. Hence, the study aimed to answer the research questions mentioned and discussed in section 1.3 of Chapter 1. Considering the results, it could be suggested that decayed root systems from the rows of plants, soil cracks, small channels and openings created by small animals, as well as slope orientation and, therefore, soil composition, all played a major role in influencing the ability of the soil to absorb the simulated rainfall. In this study, the factors that influenced run-off are micro topography, soil moisture, root system, animal activities in soil profile, soil crack dimensions and the hydraulic conductivity. The main factors that played a major role to influence sediments mobilisation are strongly believed to be the micro topography within the ring, slope gradient and length, vegetation cover and rainfall-simulation intensity. After using different techniques, the results show that farmers must be aware that with storm rainfall, particles smaller than 65 μm are subject to mobilisation. It is important to let land-users know that they need proper and appropriate methods for land-use. / South Africa