Our success stories.
GreenLED — Alphen aan den Rijn pioneers safe rainwater reuse for urban greening
Client: City of Alphen aan den Rijn
Partners (in NL): TU Delft, APRIA Systems, Aveco de Bondt
Funding: EU LIFE program
Year: 2023–2027
Problems solved: Heat stress and flooding in dense city centre, seasonal mismatch between rainfall and irrigation demand, unsustainable potable water use for green infrastructure, limited underground storage space, water safety requirements for close-contact urban use
Rainwater reused for: Irrigation of green roofs and facades
Impact: 15 million liters/year of drinking water saved; 50,000 m² of green roofs and facades supplied; rainwater captured from 31,000 m² of paved surfaces
Maassluis redirects stormwater underground using gravity-fed infiltration to reduce sewer load and flooding
Client: Municipality of Maassluis
Partners: Maassluis Rainproof, Gemeente Maassluis, Delftland, Gebeidsmanagers, Kroes Aannemingsbedrijf
Year: 2021–2022
Problems solved: Urban flooding, insufficient drainage capacity, climate adaptation pilot
Rainwater reused for: Deep underground infiltration (groundwater recharge via infiltration wells)
Impact: 800 m³ buffer; 40 m² biofilter; 80,000 m2 catchment
Rotterdam Zoo collects rainwater from its main square to irrigate plants and cut dependence on drinking water and groundwater
Client: Diergaarde Blijdorp (Rotterdam Zoo)
Partners: Bufferblock, Hoogheemraadschap Schieland en Krimpenerwaard, Gemeente Rotterdam, TU Delft
Year: 2020–2021
Problems solved: Soil subsidence & water stagnation/flooding on main square, high drinking water demand, sewer overload
Rainwater reused for: Irrigation of tropical plants; supplement to groundwater distribution network
Impact: 7,800 m³/year reused (approx. 8 million litres/year); 9,900 m² catchment; 130 m³ buffer
Rotterdam turns a city street into an underground freshwater reserve
Client: Municipality of Rotterdam
Year: 2020–2021
Problems: Sewer overflow, climate-proofing city centre, public water awareness / education
Rainwater reused for: Deep underground storage; children's interactive hand pump; public demonstration
Impact: 4,000 m³/year reused; 10,000 m³ stored; 1,200 m² catchment
TU Delft tests climate-resilient water solutions under real urban conditions
Client: The Green Village (TU Delft campus testing ground)
Partners: VP Delta, TU Delft, Van Gelder
Year: 2020–ongoing
Problems solved: Drought & heat stress, bio-filtration R&D, testing technology in real-world (not lab) conditions
Rainwater reused for: Irrigation, cooling, toilet flushing, educational demonstration
Impact: 500 m³/year stored and reused; 1,600 m² catchment; four bio-filter configurations tested in parallel
The Hague turns park stormwater into a local water source for gardens and urban farming
Client: City of The Hague
Partners: Hoogheemraadschap Delfland, Dunea, Allied Waters, Wareco, Gebr. Van Kessel
Year: 2019–2020
Problems solved: Stormwater sewer overflow, unsustainable water management in park, urban greening
Rainwater reused for: Irrigation of community gardens and urban animal farm
Impact: 10,000 m³/year reused; 35,000 m³ stored; 8,500 m² catchment
Pijnacker-Nootdorp stabilizes a sinking district with a self-sustaining water buffer
Client: City of Pijnacker-Nootdorp
Partners: KWR, Aveco DeBondt, Geoinfra, Van Kessel Wegenbouw
Year: 2018–2026
Problems: Soil subsidence, unstable groundwater levels, drying peat, climate-proofing
Rainwater reused for: Stable groundwater levels, cooling, children's play water
Impact: 16,000 m³/year reused; 46,000 m³ stored; 45,500 m² catchment
Rotterdam builds a waterbuffer that irrigates Sparta Stadium’s football pitch
Client: City of Rotterdam
Partners: KWR Water, CODEMA Group, Van Gelder
Year: 2018
Problems solved: Flooding during heavy rainfall in Spangen district, drinking water overuse for sports field irrigation, water quality (iron, PAHs, nutrients)
Rainwater reused for: Irrigation of the Sparta football pitch
Impact: 15,000 m³/year reused; 25,000 m³ stored; 1,400 m³ buffer; 40,000 m² catchment