Stormwater Overflow Tank With Feed Pump Station in "Dresden-Kaditz"

View from west with solar power system

View from west with solar power system

Project description

A stormwater overflow tank was built by order of the municipal sewerage company of Dresden on the site of the Dresden-Kaditz wastewater treatment plant. The tank has a useful volume of 24,000 m³. The tank is fed by a pump station with a maximum feed volume of 9.0 m³/s. The stormwater overflow tank is designed in such a way that it may also be used in case of special events (emergency tank upstream of the treatment plant). The feed and discharge canals to the tank were implemented at a depth of up to 10 m in a closed construction.
As the complex of tank/pump station represents the necessary replacement for the previous stormwater relief method, it needed to be integrated, hydraulically and structurally, directly into the system of the Dresden-Kaditz wastewater treatment plant. The separating structure, for instance, was fitted into to a barrel vault c. 5 m in width.

Taking into consideration the conditions prevailing at the location as well as different aspects such as investment and operating costs, maintenance- and user-friendliness, emission protection, architectural design, impact on neighbouring buildings and construction technology, the possible partial solutions for the tank complex, the feed pump station, and the feed and discharge canals were investigated and optimised in an efficient unit.

Owing to the technological requirements of the individual components, the sheeting system made use of both intersected bore pile walls and support pile walls (Berlin sheeting).

The green flat roof (area 3,120 m²) and two sloping roof areas (550 m²) were used to fit 950 solar modules. The installed modules are each 1.52 m² in size, making for an overall system of 1,444 m²: the largest solar power installation in the state capital Dresden.

This saves the municipal sewerage company energy costs. The total annual yield is around 160,000 kWh. This quantity represents the average energy consumption of 75 families of four. The electricity produced in the solar modules is converted to AC and fed into the treatment plant network via a meter. The total derivable annual yield is around 86,500 EUR (net).

Even more important is the ecological aspect: the annual reduction of emissions of CO2 is around 160 t, SO2 160 t and NOx 270 kg.

Services

Our planning office was commissioned with all phases of the planning as well as the on-site construction management.

Technical data

  • tank volume: 24,000 m³
  • maximum feed volume: 9.00 m³/s
  • number of pumps: 9
  • reservoir chambers: 6

Capital expenditure

EUR 16.1m 

Client

Landeshauptstadt Dresden, Stadtentwässerung

Time schedule

Planning period: 1999 - 2001
Construction period: 2001 - 2004