Unified Urban Drainage | Methods

Flooding happens when the water flow entering a sewer exceeds its capacity; the function of Unified Urban Drainage , is to reduce the impact that the surface water drainage system of one site has on other sites.

If UUD was universally incorporated, urban sewer flooding would be less of a problem. Unlike traditional urban storm water drainage systems, UUD protects and enhances ground water quality.

In urban areas, management of water is difficult, it requires the planning of management strategies & pollution control measures. That can be done only after identifying the sources of diffuse pollution; Traditional drainage has many disadvantages and increases the risk of flooding containing contaminants.

UUD from our partners, Evzin & Associates has been developed to collect, store and filtrate the first runoff before it enters the environment. The design standards for UUD from Evzin & Associates contains;

Filter strips and swales;

- Swales are either a natural depression or wide shallow ditches which are used to store and route the run-off.

- The swale contains a filter strip of vegetation, for removing sediment, organic matter and pollutants from the runoff.

Filter drains and permeable surfaces;

- Applied to control the storm water pollution from urban runoff.

- Permeable Pavement Systems (PPS) are most desirable for residential, commercial and industrial areas.

- The filter drains and permeable surfaces collect, treat and filtrate any urban runoff and enhance groundwater recharge.

- The treated storm water from PPS is discharged into the UUD.

Infiltration devices and basins and ponds;

- Designed and developed for the treatment of urban runoff, including wetland, ditches, ponds and detention basins.

- Wetlands for storm water are created by growing marshy plants.

- The pollutants are removed by biological and wetland uptake, retention and settling.

- Detention ponds holds water for up to 24-28 hours resulting in gravitational settlement of urban pollutants.

Retention ponds;

- The pollutants degrade and the algae and plants uptake the nutrients for 14-21 days.

- The characteristics are similar to retention basins apart from the vegetation has a shallow water zone.