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Pavement subsurface drainage systems (PSDS) are designed to drain the entrapped water out of pavement. To investigate the effects of various factors on the performance of PSDS, three dimensional models were developed using the finite element method to simulate the unsaturated drainage process in pavement. The finite element models were calibrated using the field information on outflow, peak flow, layer saturations, and time to drain. Through a series of parametric analyses, the factors that significantly influence the performance of PSDS were screened out, and a set of recommendations were made to improve our current drainage practices.The effects of pavement geometry on drainage were studied in this research. The analysis results indicate that edgedrain system can significantly improve the drainage efficiency of a pavement. The drainage performance of a pavement is mainly affected by the geometric factors that related to the edgedrain itself and the geometric factors related to the driving lanes have very limited effects.To investigate the influences of the properties of various pavement materials, some physical-empirical equations were developed in this research. These equations were used to predict the material hydraulic properties from their grain-size distributions and aggregate/asphalt contents. The analysis results of the models with various material properties indicate that the use of permeable base is effective in improving the drainage ability of a pavement. The performance of PSDS is not only affected by material permeability but also by their waterretention ability. The pavement works as an integrated hydraulic system and the hydraulic compatibility of materials must be considered in the PSDS design.The effects of climatic factors on pavement drainage were also studied in this research. A method was developed in this research to numerically describe the rainfall events. The analysis results of the models under various rainfall events indicate that rainfall duration is a more important parameter than the rainfall quantity in influencing the pavement drainage. Based on the analysis results, regression equations were developed for the estimation of pavement drainage. Finally, for design application purpose, a series of tables were included in this report to help with proper selected of pavement drainage options.

Among other sources of uncertainties in hydrologic modeling, spatial rainfall variability, channel hydraulic variability, and model parameter uncertainty were evaluated. The Monte Carlo and Harr methods were used to assess 90% certainty bounds on simulated flows. The lumped watershed model, Hydrologic Simulation Program FORTRAN ? HSPF, was used to simulate streamflow at the outlet of the Luxapallila Creek watershed in Mississippi and Alabama. Analysis of parameter uncertainty propagation on streamflow simulations from 12 HSPF parameters was accomplished using 5,000 Monte Carlo random samples and 24 Harr selected points for each selected parameter. Spatial rainfall variability propagation on simulated flows was studied using six random grid point sets of Next Generation Weather Radar (NEXRAD) rainfall data (i.e., 109, 86, 58, 29, 6, and 2 grid points) from the baseline scenario (115 NEXRAD grid points). Uncertainty in channel hydraulic properties was assessed comparing the baseline scenario (USGS FTABLE) versus the EPA RF1 FTABLE scenario. The difference between the baseline scenario and the remaining scenarios in this study was evaluated using two criteria: the percentage of observed flows within the HSPF 90% certainty bounds (Reliability) and the width of the HSPF 90% certainty bounds (Sharpness). Daily observed streamflow data were clustered into three groups to assess the model performance by each class: below normal, normal, and above normal flows. The parameter uncertainty propagation results revealed that the higher the model Sharpness the lower the model Reliability. The model Sharpness and Reliability results using 2 NEXRAD grid points were markedly different from those results using the remaining NEXRAD data sets. The hydraulic property variability of the main channel affected storm event paths at the watershed outlet, especially the time to peak flow and recessing limbs of storm events. The comparison showed that Harr?s method could be an appropriate initial indicator of parameter uncertainty propagation on streamflow simulations, in particular for hydrology models with several parameters. Parameter uncertainty was still more important than those sources of uncertainty accomplished in this study because all of the median relative errors of model Reliability and Sharpness were lower than +/- 100%.

In this thesis I examine and explore whether and if Integrated Water Resources Management (IWRM) inspired water reforms respond to- and address the diverse realities of women and men in informal (and formal) rural economies of Sekororo, South Africa and Ward 17 in Gwanda, Zimbabwe which are both in the Limpopo basin. South Africa and Zimbabwe, like other southern African countries, embarked on IWRMinspired water reforms, culminating in the promulgation of the National Water Acts in 1998, four years after the attainment of South Africa’s democracy in 1994 and 18 years after Zimbabwe attained independence in 1980. I argue that the adoption of IWRM, which emphasises second generation water issues such as demand management, water quality, environmental flow requirements etc, and not the development of water infrastructure, begs the question whether such reforms can make a meaningful contribution to the development agenda in countries where, during apartheid and colonialism, the water rights (among other rights) of millions of blacks were compromised because of unjust legislation and skewed underinvestment in water infrastructure

In this thesis I examine and explore whether and if Integrated Water Resources Management (IWRM) inspired water reforms respond to- and address the diverse realities of women and men in informal (and formal) rural economies of Sekororo, South Africa and Ward 17 in Gwanda, Zimbabwe which are both in the Limpopo basin. South Africa and Zimbabwe, like other southern African countries, embarked on IWRMinspired water reforms, culminating in the promulgation of the National Water Acts in 1998, four years after the attainment of South Africa’s democracy in 1994 and 18 years after Zimbabwe attained independence in 1980. I argue that the adoption of IWRM, which emphasises second generation water issues such as demand management, water quality, environmental flow requirements etc, and not the development of water infrastructure, begs the question whether such reforms can make a meaningful contribution to the development agenda in countries where, during apartheid and colonialism, the water rights (among other rights) of millions of blacks were compromised because of unjust legislation and skewed underinvestment in water infrastructure

Philosophiae Doctor - PhD / In this thesis I examine and explore whether and if Integrated Water Resources Management (IWRM) inspired water reforms respond to- and address the diverse realities of women and men in informal (and formal) rural economies of Sekororo, South Africa and Ward 17 in Gwanda, Zimbabwe which are both in the Limpopo basin. South Africa and Zimbabwe, like other southern African countries, embarked on IWRM inspired water reforms, culminating in the promulgation of the National Water Acts in 1998, four years after the attainment of South Africa's democracy in 1994 and 18 years after Zimbabwe attained independence in 1980. I argue that the adoption of IWRM, which emphasises second generation water issues such as demand management, water quality, environmental flow requirements etc, and not the development of water infrastructure, begs the question whether such reforms can make a meaningful contribution to the development agenda in countries where, during apartheid and colonialism, the water rights (among other rights) of millions of blacks were compromised because of unjust legislation and skewed underinvestment in water infrastructure. / South Africa