Sanitation planning by analyzing the DEWATS potential in urban settlement structures : a way to improve the water quality of the Havana Bay

Abstract

Havana is experiencing many challenges which are often explained by the economical situation and the fast urbanization.But aside from the economical issues, it got over the last centuries clearer that the sanitation related topics, such as wastewater management, emerge as one of the biggest challenges for the city. A huge part of the domestic wastewater is discharged into the nearby rivers and streams that run into the Havana Bay without any form of treatment. As a result the aquatic environment is highly polluted and public health in risk.

There is an urgent need for alternative wastewater treatment approaches since the existing infrastructure is obsolete which is why it often fails. Furthermore, conventional centralized wastewater treatment plants appear to be difficult to realize because of missing means and materials.

The concept of sustainable sanitation using technologies such as DEWATS represents an appropriate solutions and has already been practiced successfully by the Bremen Overseas Research and Development Association (BORDA). However, the city has different urban settlement structures with different local conditions. For that reason this master thesis focuses on the analysis of the DEWATS potential in settlement structures of Havana to find out if this could be an appropriate solution to improve the water quality if the Havana Bay and its tributaries.

In a first part the situation of sanitation related aspects in the study area is given and existing strategies on the local as well as international level are presented. Case studies from other countries with similar problems show how sustainable sanitation can depict a solution possibility to handle the treatment of wastewater in an efficient way.

In the next part the solution concept for Havana is assessed. To figure out which technology combinations seem appropriate and bring the best possible outcomes, the improvement of the water quality in the Bay and its tributaries, it was necessary to define settlement structure types and to analyze the technologies. The results are applied to local case examples in the study area and afterwards assessed. Based on that method vague estimations for the treated wastewater are calculated and predictions about the effectiveness of the solution concept are given.