Aquifers of the urban conglomerates in the southwestern coastal Bangladesh—situated at the heart of the Ganges delta—are susceptible to contamination and induced saltwater intrusion because of population pressure demanding for freshwater and other anthropogenic interventions and thus are vulnerable in terms of quality and quantity. This comprehensive review endeavours to elucidate the geochemistry of solute load of such aquifers for its monitoring, management and conservation. One hundred and seventy numbers of groundwater samples from the production tube wells, penetrating mostly the shallow coastal alluvial aquifers, collected in different periods from Bagerhat, Faridpur, Jhenaidah, Paikgacha and Satkhira municipalities and Khulna City Corporation (KCC) are analyzed for major cations and anions following standard methods. The results show that the abundance of cations follow the general trend Na>Ca>Mg>K for Bagerhat, Paikgacha and KCC and Ca>Mg>Na>K for Satkhira, Jhanaidah and Faridpur municipalities. The anions on the other hand follows the general trend of HCO₃>Cl>SO₄>PO₄ for Satkhira, Jhenaidah, Faridpur and KCC and Q>HCO₃>SO₄>PO₄ for Bagerhat and Paikgacha. The spatial variation of soute load to the aquifers is statistically quite significant. Molar ionic ratio of chemical parameters suggests both carbonates and plagioclase silicates as their source rock. However seawater intrusion to the aquifers is quite revealing, may be due to localized upwelling of saline waters. Most of the groundwater is supersaturated with respect to both calcite and dolomite suggesting absence of nucleation for calcite precipitation.

The chemical mechanism responsible for the groundwater chemistry is rock weathering, however, is gradually commanded by the processes of evaporation and crystallization as is evident from Gibb's plot. The water type is both Na-HCO₃ and Na-Cl for Bagerhat and Paikgacha while it is mostly Ca-Mg-HCO₃ for Faridpur, Satkhira, Jhenaidah and KCC. Further most of groundwater from Faridpur, Satkhira and Jhenaidah occupies temporary hardness field of Chadha's plot. Almost all samples from Paikgacha and most samples from Bagerhat are saline as revealed from Chadha's plot. With respect to TDS, groundwater in most municipalities of southwestern coastal Bangladesh does not accord with standard and in few cases such as in Faridpur and Paikgacha almost 100% of the samples exceed desirable limit for safe drinking. From published reports on consequences of rapid climate change it may be envisioned that salinity front would move upwards and drainage congestion would increase which would create uncertainty in groundwater management. Thus conjunctive use of groundwater with surface water may be prescribed at this moment.