By Albert Reinaldo (Thesis M.Sc. Unesco-IHE, Netherlands – Thesis M.Si Sriwijaya University, 2011), Supervised by Prof. Bart Schultz, PhD, MSc; Prof. Dr. Robiyanto Hendro Susanto, M.Agr.Sc.; F.X. Suryadi, PhD, MSc.

Since ancient times, flooding has become a regular and a common disaster in Jakarta that makes enormous in various sectors, for instance environment, business, and society. Most of the floods about 40% of Jakarta area such as in the North Jakarta are caused by overflowing of a huge mass of water to lowland areas because water bodies such as rivers, streams, lakes and canals cannot collect sufficiently the accumulation of water when heavy rainfall occurs. Papanggo Area is situated in lowland area also suffers from flooding.

A flood in an urban area can be considered as a natural hazard when the nature influences the flood such as heavy rainfall and high tide. A flood can be considered as man-made causes if the river or drainage systems cannot work as usual due to system disturbance by human for example, the land subsides due to groundwater extraction; water flow is blocked by garbage and changing of the land use.

The thesis research has been carried out to study urban drainage and flood protection system in the Papanggo Area in North Jakarta using hydrology, hydraulics and spatial modelling techniques (the DUFLOW and GIS).

To achieve the objective, simulating scenarios were used as follows:

• Scenario 1 : the urban drainage represents the existing conditions and has been uses as the basic case. Under Scenario 1, the existing urban drainage was considered as one system;
• Scenario 2 : design urban canal profiles were used. Under scenario 2, alternative in mitigating flood were applied;
• Scenario 3 : as the scenario 2, but were investigated; also tidal fluctuation and the effect of the land subsidence for 25 years from nor;
• Scenario 4 : proposed development.

Mitigation scenarios of both structural and non-structural measures were evaluated in flooding areas. For structural measures, three alternatives of design urban canal profile and one for proposed development considering land use and sea level rise were studied.

A polder with its water management and flood protection system can be one of the solutions for flooding problem in the Papanggo Area. Then for non-structural measures, several measures would have to be implemented in order to eliminate or to minimize adverse such as local society organization, public awareness campaigns, spatial plan implementation, a flood forecast-warning system, flood hazard mapping and a database, a disaster recovery plan, structural organization, legislation-law enforcement and also operation-maintenance of urban polder water management are proposed.

In order to make benefit cost analysis, the alternatives studied have been calculated as project cost; and material losses were calculated as a benefit after doing projects. The alternative 1 was chosen as alternatives for urban drainage design profiles.