This research examined the levels of heavy metals in boreholes and hand dug wells within Kashere town and environs. The sampling was carried out at 10 locations in Kashere area of Gombe state. Five samples were collected from boreholes and five from hand dug wells and analyzed for some heavy metals (copper, cadmium, chromium, lead, nickel and manganese) using Atomic Absorption Spectrophotometer (AAS). The result shows that there is high concentration of most of the heavy metals in the groundwater samples with Pb, Ni, Cr, and Cd having mean concentrations above the maximum limit set by W.H.O. It was recommended that a systematic treatment of heavy metals concentration in groundwater sources in the study area be carried out regularly either through; Chemical precipitation, ion exchange or Reverse osmosis.

The Middle zone aquifer is the most extensive and most widely exploited of the three well known aquifers of the Chad Formation. This aquifer is confined by variable thickness of argillaceous deposits of 100-150 m thick. This led to the variable heads in boreholes drilled to this zone. Boreholes drilled from 1960 to 2010 shows a drastic decline in piezometric heads. The piezometric heads of over 20 m above ground level (agl) observed in 1960 to 1.2 m agl in 2010 have declined over the last half century. In the present work the heads at 0.2 m/ year giving the present piezometric head at an average of 0.5 m agl. The lower heads in old boreholes are attributed due to siltation, encrustation and ageing of borehole. Furthermore, lack of present day recharge and poor borehole construction methods play a vital role in determining the piezometric head.

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