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Rainfall, evaporation and temperature data of Owerri for ten years (Figure 1) (1998-2007) were acquired. The data were analyzed using standard statistical measures and climatological normal (Figure 2). The results show that the rainfall pattern exhibits some oscillations indicating annual bimodal distribution of rainfall. The temperature reached its lowest value of 27.75?C in 1999. Thereafter, a steady increase in temperature was noticed. From 2002, some variation in evaporation data was observed. The potential evapotranspiration shows some correlation with temperature. This variation in weather parameters may be attributed to climate change

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A combination of geoelectric and hydrogeologic concept was used in the assessment of groundwater vulnerability in fractured aquifers of Oju and environs. The study area is underlain by the sediments of the Asu River Group, Southern Benue Trough Nigeria. A total of twenty-seven (27) Vertical Electrical Sounding (VES) was carried out within the study area. Geoelectric parameters (layer, resistivity and thickness) of the overlying layers across the study area were determined and used to evaluate the vulnerability of the underlying aquifers. Three charts were compared using geo-electrically derived models; LC (Longitudinal Conductance), GLSI (geoelectric layer susceptibility indexing) and GOD (groundwater occurrence, overlying lithology and depth to the aquifer. Results obtained from LC revealed that the study area fell within the moderate category, GLSI showed that aquifer vulnerability were categorize within negligible to low category and GOD fell within low to moderate category. On the average, groundwater within the study area is considered moderate vulnerable to groundwater contamination.

The geoelectrical investigation of the proposed Aba River dam at Amapu-Ideobia, Akanu Ngwa Southeastern Nigeria has been carried out. The objective of this study is to determine the downward and lateral trends of the rock layers or units along and near the proposed dam axis and deduce the possible structures that may enhance workable design of the dam. ABEM Terrameter SAS 4000 model was used and the symmetrical Schlumberger configuration was adopted. Twelve (12) Vertical Electrical Sounding stations were located and fully occupied along the dam axis. Preliminary input data from the field were fed into Zohdy software to generate real resistivities and depths to geoelectric layers. Five geoelectric layers were interpreted as Loamy Top soil, Alluvial matter, Pebble bed, Sandy lateritic and Gravely sand. Layer 1 (the top loamy soil) was encountered in VES 1, 2, 3, 4, 5, 9, 10, 11 and 12 locations with maximum thickness of 1.5 m in VES 3 and 4. Resistivity values ranged from 216 to 519 Ohm-m. The second layer (lateritic matter) had a maximum lower depth of 5 m in VES 3 and 4 points. This was not encountered in VES 6 point being replaced by alluvium. Resistivity values ranged from 101 to 6190 Ohm-m. Layer 3 was interpreted as a restricted pebble bed which occurred only at VES 6, 7 and 8 locations flanking the river course with thickness of about 3.5 m and resistivity values range of 182 -415 Ohm-m. The fourth layer was modeled as the alluvial matter and restricted to the river course (VES 6,7, 8) locations with base at between 12.5 m in VES 8 and 8 m in VES 6. The last modeled layer (Layer 5) was composed of gravely sandstone that underlined the whole study area apart from the restricted pebble bed at the NE crestal portion (VES 12). No structures like fractures, lineaments and faults that would be of deleterious effect were observed in all the VES points down to about 40 m. However, it was observed that the axial length had overriding sandy matter with high porosity and potentially rife for great infiltration; a condition that could facilitate seepage around the reservoir portion of the dam.