Andrew Ako

Evaluation of groundwater quality and its suitability for drinking, domestic, and agricultural uses in the Banana Plain (Mbanga, Njombe, Penja) of the Cameroon Volcanic Line

Groundwater quality of the Banana Plain (Mbanga, Njombe, Penja—Cameroon) was assessed for its suitability for drinking, domestic, and agricultural uses. A total of 67 groundwater samples were collected from open wells, springs, and boreholes. Samples were analyzed for physicochemical properties, major ions, and dissolved silica. In 95% of groundwater samples, calcium is the dominant cation, while sodium dominates in 5% of the samples. Eighty percent of the samples have HCO3 as major anion, and in 20%, NO3 is the major anion. Main water types in the study area are CaHCO3, CaMgHCO3, CaNaHCO3, and CaNaNO3ClHCO3. CO2-driven weathering of silicate minerals followed by cation exchange seemingly controls largely the concentrations of major ions in the groundwaters of this area. Nitrate, sulfate, and chloride concentrations strongly express the impact of anthropogenic activities (agriculture and domestic activities) on groundwater quality. Sixty-four percent of the waters have nitrate concentrations higher than the drinking water limit. Also limiting groundwater use for potable and domestic purposes are contents of Ca2+, Mg2+ and HCO3− and total hardness (TH) that exceed World Health Organization (WHO) standards. Irrigational suitability of groundwaters in the study area was also evaluated, and results show that all the samples are fit for irrigation. Groundwater quality in the Banana Plain is impeded by natural geology and anthropogenic activities, and proper groundwater management strategies are necessary to protect sustainably this valuable resource.

Water quality assessment in the Bétaré-Oya gold mining area (East-Cameroon): Multivariate Statistical Analysis approach

The influence of gold mining activities on the water quality in the Mari catchment in Bétaré-Oya (East Cameroon) was assessed in this study. Sampling was performed within the period of one hydrological year (2015 to 2016), with 22 sampling sites consisting of groundwater (06) and surface water (16). In addition to measuring the physicochemical parameters, such as pH, electrical conductivity, alkalinity, turbidity, suspended solids and CN-, eleven major elements (Na+, K+, Ca2+, Mg2+, NH4+, Cl-, NO3-, HCO3-, SO42-, PO43- and F-) and eight heavy metals (Pb, Zn, Cd, Fe, Cu, As, Mn and Cr) were also analyzed using conventional hydrochemical methods, Multivariate Statistical Analysis and the Heavy metal Pollution Index (HPI). The results showed that the water from Mari catchment and Lom River was acidic to basic (5.40<pH<8.84), weakly mineralized (6.3<EC<160.8μS/cm) and had a high concentration of total suspended solids (TSS) (2<TSS<8996.00mg/L). The major elements were all within the World Health Organization (WHO) guidelines for drinking water quality, except for nitrates in some wells, which was found at a concentration >50mg NO3-/L. This water was found as two main types: calcium magnesium bicarbonate (CaMg-HCO3), which was the most represented, and sodium bicarbonate potassium (NaK-HCO3). As for trace elements in surface water, the contents of Pb, Cd, Mn, Cr and Fe were higher than recommended by the WHO guidelines, and therefore, the surface water was unsuitable for human consumption. Three phenomena were responsible for controlling the quality of the water in the study area: hydrolysis of silicate minerals of plutono-metamorphic rocks, which constitute the geological basement of this area; vegetation and soil leaching; and mining activities. The high concentrations of TSS and trace elements found in this basin were mainly due to gold mining activities (exploration and exploitation) as well as digging of rivers beds, excavation and gold amalgamation.

Access to potable water and sanitation in Cameroon within the context of Millennium Development Goals (MDGS)

Cameroon has been fully engaged with the Millennium Development Goals (MDGs) since their inception in 2000. This paper examines the situation of access to potable water and sanitation in Cameroon within the context of the Millennium Development Goals (MDGs), establishes whether Cameroon is on the track of meeting the MDGs in these domains and proposes actions to be taken to bring it closer to these objectives. Based on analyzed data obtained from national surveys, government ministries, national statistical offices, bibliographic research, reports and interviews, it argues that Cameroon will not reach the water and sanitation MGDs. While Cameroon is not yet on track to meet the targets of the MDGs for water and sanitation, it has made notable progress since 1990, much more needs to be done to improve the situation, especially in rural areas. In 2006, 70% of the population had access to safe drinking water and the coverage in urban centres is 88%, significantly better than the 47% in rural areas. However, rapid urbanization has rendered existing infrastructure inadequate with periurban dwellers also lacking access to safe drinking water. Sanitation coverage is also poor. In urban areas only 58% of the population has access to improved sanitation facilities, and the rate in rural areas is 42%. Women and girls shoulder the largest burden in collecting water, 15% of urban and 18% rural populations use improved drinking water sources over 30 minutes away. Cameroon faces the following challenges in reaching the water and sanitation MDGs: poor management and development of the resources, coupled with inadequate political will and commitment for the long term; rapid urbanization; urban and rural poverty and regulation and legislative lapses. The authors propose that: bridging the gap between national water policies and water services; recognizing the role played by Civil Society Organizations (CSOs) in the attainment of MDGs; developing a Council Water Resource Management Policy and Strategy (CWARMPS); organizing an institutional framework for the water and sanitation sector as well as completion and implementation of an Integrated Water Resources Management (IWRM) plan, would bring Cameroon closer to the water and sanitation MDGs.

Variation of hydrogeochemical characteristics of water in surface flows, shallow wells, and boreholes in the coastal city of Douala (Cameroon)

ABSTRACT Groundwater is used by 3 million inhabitants in the coastal urban city of Douala, Cameroon, but comprehensive data are too sparse for it to be managed in a sustainable manner. Hence this study aimed to (1) assess the potability of the groundwater; (2) evaluate the spatial variation of groundwater composition; and (3) assess the interaction and recharge mechanisms of different water bodies. Hydrogeochemical tools and methods revealed the following results in the Wouri and Nkappa formations of the Douala basin, which is beneath Douala city: 30% of water samples from hand-dug wells in the shallow Pleistocene alluvium aquifer were saline and highly mineralized. However, water from boreholes in the deeper (49–92 m depth) Palaeocene aquifer was saline-free, less mineralized and potable. Water in the shallow aquifer (0.5–22 m depth) was of Na+-K+-Cl−-NO3− type and not potable due to point source pollution, whereas Ca+-HCO3− unpolluted water dominates in the deeper aquifer. Water in the deep and shallow aquifers indicates the results of preferential flow pass and evaporative recharge, respectively. Possible hydrogeochemical processes include point source pollution, reverse ion exchange, remote recharge areas and mixing of waters with different chemical signatures. EDITOR D. Koutsoyiannis ASSOCIATE EDITOR M.D. Fidelibus