5. Water Pollution Control Centre, Tubli, Bahrain

SYNOPSIS. A very large sewage treatment works covering some

24 hectares of reclaimed land was proposed. Ground conditions

consisted of about 2m of uncompacted hydraulic fill (sand)

overlying up to 4m of silty sand followed by "caprock" and

layers of sand, marl and mudstone. The water table was within

lm of the ground level. It was not noticeably affected by tidal

movements. Because of the nature of the interconnected struc

tures comprising the plant and the probability of high total

and differential settlements it was essential to estimate them

as closely as possible in order to avoid the risk of reversed