Low cost adsorbents have become a major area of consideration to many researchers due to the expense nature of the available activated carbon. Although commercial activated carbon is the most sufficient and efficiently used carbon for the removal of heavy metals ions coming from wastewater, it is faced with a lot of setback such as; the higher the quality of the activated carbon the more expensive it is, the regeneration of the used carbon tends to be very difficult especially in large volume. Due to this different biomass from agricultural by-products have been investigated to replace the commercial activated carbon and most of the findings have indicated a significant removal in terms of heavy metals in synthetic aqueous solution. This study have looked into and reviewed the various low cost adsorbents that have been employed for the treatment of wastewater laden with heavy metals.

A moderate rainfall event can lead to harsh flash floods in most of the compact cities. Present urbanization happening in these cities creates an imbalance between generated urban runoff volume and effective drainage capacity. For the survival of these, it is vital in enhancing the efficiency of an urban drainage system. However, it is a complicated task due to the accumulation of solid waste in drainage channels. These drainage systems are super sensitive to some external factors caused by their immediate surroundings. This study found out the impact of the urban form, population agglomeration, floating population, imminent prone areas of urban sprawl and waste disposing patterns of settlers can be highly influenced to the efficiency of a storm drainage system. Hence, Geographical Information System based computational techniques and weighted fussy sets are being used to track the attention need areas of the system. These particular zones to be treated through the design of "Smart Storm Drainage Unit". By this, it is expected to maintain a clear drainage channel for transportation of surface runoff all the time. Thus, by Smart Storm Drainage will be fixed into the breakdown areas or highly sensitive areas of a drainage system. This paper discusses the impact of surrounding urban area to the breakdown of drainage system and fixates the problem by bypassing “Smart Storm Drainage Unit”.