REFERENCES

FOR THE PROTECTION OF OUR WATERS

Retrofitting two filter systems – Bremer Straße B 75

On Bremer Straße (B75) in Hamburg Harburg, an existing rainwater treatment plant, which was financed from compensation funds for the construction of a power station, funds from the nature conservation department (Harburg district office for civil engineering and urban greenery) and funds from the authority for urban development and the environment (water protection department), was retrofitted with two filter systems from 3P Hydrosystem.

These systems were installed in one of the existing filter shafts in December 2006. The water from around 2,300 m² of road surface, consisting of the main road with a high proportion of HGVs in the area of a traffic light and a bus turning point, is initially fed into a sludge trap. From there, it flows via a distribution shaft into the filter shaft and via a sampling shaft into the Eißendorfer Forst biotope.

Results
Since the filter systems were installed, samples of the system have been taken at approximately one-month intervals during rain events over a period of three years. A volume of around 5400 m³ of road runoff was treated. Two measuring systems were used to determine the level of water pressure on the filters and the flow rate through the system. Since, in contrast to the original design of the filter system, more than twice the impermeable area was connected, around 5 % of the annual runoff volume was not treated by the filters but routed via a bypass.

The efficiency of the system is between 80 % and 90 % for the heavy metals copper, lead, zinc and cadmium, 92 % for filterable substances, 80 % for phosphorus compounds, 65 % for nitrogen compounds and 85 % for mineral oils. This means that even the strict test values of the Federal Soil Protection and Contaminated Sites Ordinance for the soil-groundwater pathway are met.

Year of construction: 2006
Type of connected areas: Federal road and bus turning lane
Area size: approx. 2,300 m²
Filter system: 2 hydro systems 1,000 Heavy Traffic

Daniel Betschner,
Master Professional of
Technical Management (CCI)
Project Engineer

Tel +49 (0) 7334 92460-32
Mail betschner@3ptechnik.de