WATER RESOURCES USE, ABUSE AND REGULATIONS IN NIGERIA

The evolvement processes of water laws in Nigeria, as well as their efficiency in the sustenance of surface water resources, were studied. A cursory look was also taken into the mode of access to water resources by households in Nigeria. This was done vis-à-vis the governmental effort at providing potable water for its teeming population as well as the Land Use Act of 1978, which vests absolute control and ownership of all water resources, ground and surface, in the land owner. About 47 million Nigerians still rely, exclusively, on surface water sources to meet their domestic needs. Yet, pollution discharge into the surface water by individuals and industries go on unmitigated, unregulated, and unpunished due to weaknesses in the existing laws. The involvement of the scientific community in the regular calibration and monitoring of surface water quality as a tool for managing the surface and groundwater resources, among other things, would be an advantageous tool for curbing the pollution menace

An Evaluation of Slaughterhouse Wastes in South-West Nigeria

This study was carried out at ten randomly selected slaughterhouses situated in Lagos and Ogun States, Nigeria. The aim was to evaluate the current waste generation and waste handling practices while exploring the possibility of reducing to the barest minimum the percentage of live weight cow that is considered as waste. This was achieved through questionnaire application, live interviews, literature review and physical inspection. It was shown that just 5 % of the total slaughtered animal weight, arising from bovine blood, dung and undigested paunch contents, coupled with the large volume of water required to wash off this small percentage of animal parts constituted the greatest proportion of environmental problems associated with slaughterhouse operations. Ways through which these waste materials could be converted into wealth, thereby relieving the environment from their harmful effects were suggested

Study of Auto Purification Capacity of River Atuwara in Nigeria

The aim of this paper was to study and predict the self-purification capacity of River Atuwara. This was done primarily by measuring the Dissolved Oxygen (DO) downstream of a pre-selected pollution discharge point on River Atuwara and then predicting the same using the modified Streeter-Phelps equations. Other data gathered from each of the 17 sampling stations on River Atuwara and used in the analysis included Biochemical Oxygen Demand, (BOD), pH, stream velocity, stream depth and distance. Predicted DO deficit trend lines were first fitted by retaining the original re-aeration coefficient component, k2, of the modified Streeter-Phelps equation (USGS equation) and subsequently by substituting it with Atuwara reaeration coefficient model. It was found that the latter displayed better predictive capacity. Results also demonstrated that the auto-purification capacity of the river which is already limited by the relatively low DO saturation level is further threatened by the wastes being discharged into it at varying intervals. Some of the wastes which are non-biodegradable and acidic were also found to be interrupting the auto-purification processes of the river. Water from River Atuwara requires treatment before it can be considered safe for consumption by its current users

Hydro-geometrical data analyses of River Atuwara at Ado-Odo/Otta, Ogun State

The dataset analyzed in this article contains spatial and temporal values of the hydro-geometric parameters of River Atuwara. The hydro-geometrical data analyses of various sampling point on River Atuwara was examined and their geometric properties were taken with the use of a paddled boat,depth meter and global positioning system(GPS).The coordinates, width, depth, slopes, area, velocity, flow were gotten in-situ while the area and wetted perimeter were computed ex-situ. The statistical relationships between separate variables were considered using scatter plots and regression line equations. Inferences drawn from various variable comparisons can be used to validate predictive models for various time seasons

Estimation of longitudinal dispersion co-efficient: A review

Accurate determination of longitudinal dispersion coefficient in rivers or streams is necessary for pollution control and management. This can be achieved through tracer studies and has proven to be a reliable method for measuring pollution spread. However, tracer studies practise which is expensive, time gulping and requiring large labour input have been substituted with empirical approaches thereby reducing the applicability of the dispersion coefficient models generated. This study reviews the various models derived as well as methods associated in the collection of tracer concentration data (measurement) existing in the literature. A sustainable approach to this study was identified and research needs were also listed

Evaluation of reactivity indexes and durability properties of slag-based eopolymer concrete incorporating corn cob ash

The method of determining the quantities of geopolymer concrete (GPC) ingredients to attain the required and specifiable characteristics is complex owing to the involvement of more variables compared with Portland cement concrete (PCC) systems. Therefore, this study evaluated the hydraulic responses and chemical resistance of GPC produced with supplementary cementitious materials (SCMs), ground granulated blast furnace slag (GGBFS) and corn cob ash (CCA) at ambient curing conditions. Corn cob was dehydroxylated at 600 �C and used as a partial replacement for GGBFS at 0, 20, 40, 60, 80, and 100%. The activators used were 12, 14 and 16 M concentration (M) of both sodium silicate (SS) and sodium hydroxide (SH). The chemical compositions of individual and mixed binders were analyzed, while the chemical moduli of each and blended binder were examined and evaluated based on the significant reactive oxides, hence resulting in the evaluation of reactivity indexes (RIs). Moreover, the compressive strength was predicted based on the RIs and mix design proportions (MDPs) of the blended concrete, while the durability properties of each concrete sample were investigated. The results indicated that the oxide compositions of GGBFS and CCA influenced the compressive strength of GPC produced. Compared with the experimental results, the predictive compressive strengths based on the RIs and the MDPs yielded a high precision with 95% ‘‘R2”. Furthermore, the incorporation of both GGBFS and CCA increased the durability of GPC produced against sulfate attacks. Ultimately, the model equations developed by this study can be beneficial in the refinement of mix designs of both GPC and conventional concrete incorporating SCMs provided the oxide compositions of the elements are obtained

Influence of Cement, Bitumen and Lime on Some Lateritic Soil Samples as Pavement Material

This study was carried out in order to determine cement, lime and bitumen prerequisite of some lateritic soil specimens as sub base materials. Soil specimens A, B, C was collected from Dual carriageway road construction project at Estate Iwo road, Osogbo, Osun state and stabilized with 0, 3, 6, 9, and 12% of cement, lime and bitumen. Various laboratory test was conducted on the soil specimen such as California Bearing Ratio (C.B.R), Compaction, Atterberg’s limit test and particle size distribution. The investigation revealed that beneficial effects were obtained by the addition of cement, Lime and Bitumen to improve the strength of weak or poor soils. The C.B.R values are 9.88%, 4.36% and 7.27% for sample A, B and C respectively at 0% additive content and at 12% additives, the samples gave C.B.R values of 55%, 50.0% and 50.00% by using cement. All the three samples have maximum C.B.R values of 45.0% with lime as additives. For using bitumen, result gave maximum C.B.R values of 41% for sample A and B and Sample C have 40.0%. Addition of additives improved the samples from a poor subbase material to an excellent subbase material with C.B.R values over 30%. Hence, soil improvement of laterite samples from the studied site can be carried out successfully by using Lime or bitumen judging from the result of the various tests on the different soil – additive mixtures

Effect of Common Salt on the Engineering Properties of Expansive Soil

This paper investigated the effect of common salt on some geotechnical properties of expansive soil for highway pavement (subgrade) works. In this study, engineering properties including; Natural water content, Atterberg limits, specific gravity, compaction, free swell index, unconfined compressive strength, soaked and unsoaked California bearing ratio were determined in the laboratory and their behavior on stabilizing with various percentages of sodium chloride (0, 0.5, 1.0, 1.5. 2.0 and 2.5) investigated. From the study, plastic limit, liquid limit, plasticity index, linear shrinkage, specific gravity, free swell index and optimum water content values of the stabilized soil reduced, while the maximum dry density, California bearing ratio and unconfined compressive strength values increased. The highest reduction percentages of 60.42 % (131 to 51.85 %), 42.86 % (50.00 to 28.57 %), 71.26 % (81.00 to 23.28 %), 66.64 % (15.11 to 5.04 %), 83.43 % (115.00 to 19.05 %), and 28.57 % (28.00 to 20.00 %) in liquid limit, plastic limit, plasticity index, linear shrinkage, free swell index and optimum water content respectively; and maximum percentage increase of 11.38 % (1.67 to 1.86 g/m3 ,on maximum dry density), 31.78 % (29.20 to 38.48 %, on unsoaked CBR), 257.67 % (4.3 to 15.38 %, on soaked CBR), and 26.98 % ( 67.86 to 86.17 kN/m2 on unconfined compressive strength) were obtained on treatment of the soil with 1.5 % common salt by weight. Treatment of the soil with common salt has thus reduced its swelling potential and increased the strength

Self-compacting concrete in pavement construction: Strength grouping of some selected brands of cements

This paper investigates strength properties of some selected cement brands for self-compacting concrete application in pavement construction. Three brands each of Portland limestone cement grades, CEM II/A-L 42.5 (Brand A), CEM II/B-L 32.5 (Brand B) and CEM II/B-L 32.5 (Brand C), were used. Rheological test was carried out using the L-Box, V-Funnel and slump cone while compressivegas emissions from the building sector. These systems require high investments which are returned through the heat sales. Due to the changed climate conditions and building renovation policies, heat demand in the future could decreas