Hölscher Projects

Sternstraße Lingen

A new micro-apartment complex with an underground car park is being developed on Sternstraße in Lingen, the largest city in the Emsland region. Hölscher is responsible for the complete groundwater management for the construction project under challenging hydrogeological conditions.
Dewatering - reinfiltration - monitoring. A project with 100% water neutrality.

A sensitive approach to dewatering – contamination within a drinking water catchment area

A groundwater contamination site is located close to the construction project, which is also in the immediate vicinity of a drinking water catchment area. Hölscher lowered the groundwater level for the excavation and reinfiltrated the abstracted water directly behind the sheet-pile wall.
By using our hw-dsi wells, we created a hydraulic barrier that prevented the cone of depression from extending towards the contaminated groundwater area. This ensured that the groundwater contamination was not spread.

Services and technologies used

Hydraulic barrier using jet suction infiltration – a safe solution for contaminated groundwater

The particular challenge of this project lies in managing an existing area of groundwater contamination close to the construction site. As the excavation is located near a drinking water catchment area, it was essential to prevent any migration of the contaminated groundwater.
By reinfiltrating the entire pumped volume through 65 DSI wells, an effective hydraulic barrier is created. This stabilises the groundwater flow conditions, limits the drawdown and infiltration cones and reliably prevents contaminants from migrating and spreading.

System performance data – consistently stable dewatering and re-infiltration

The dewatering system was designed for high performance:

  • Maximum pumping rate: 170 m³/h
  • Average pumping rate: 130 m³/h
  • Reinfiltration: 100% of the pumped volume via 65 DSI wells
  • Capacity per DSI well: 2–3 m³/h

This ensures that the entire volume of water is reinfiltrated into the ground directly behind the sheet-pile wall — an optimal solution from both a technical and environmental perspective.

Efficient groundwater lowering using horizontal drainage

A milled horizontal drainage system was selected for the groundwater drawdown, making it ideally suited to fully sheet-piled excavations. This method ensures uniform and precise dewatering, short construction times and accurate control of groundwater levels.
In addition, localised wellpoint systems were installed for deeper foundation areas to ensure safe working conditions there as well.

Modern living space in a central location

The new micro-apartment complex offers:

  • compact, high-quality living solutions for students and professionals

  • a fully managed rental model for property owners

  • close proximity to the campus, city centre and railway station

The project therefore contributes to urban development and strengthens the housing market in the Emsland region’s largest business and university hub.

Construction project in Emsland’s largest city

The Lingen campus, city centre and railway station are all within walking distance. Completion is scheduled for spring 2027, and the construction work is progressing according to plan, thanks in part to our dewatering system.

Housing for students

The development will comprise 107 fully furnished and five partially furnished apartments, as well as 17 underground parking spaces and 27 outdoor parking spaces.

Equipment and machinery used

Drainage trencher BSV-5000

Rotomax L (for hw-dsi wells)

Hölscher Volvo FMX 330

More projects

Loading search results ...