Sustainable Drainage Systems are designed to replicate natural water drainage processes. Unlike traditional piped drainage—which rapidly channels rainwater into rivers and municipal sewers, often overwhelming local networks—SuDS slow down, store, and clean surface water before releasing it at a controlled rate back into the environment.

When JJ Gilleran Ltd partners with developers during early-stage site groundworks, three key drivers shape every drainage strategy:

• Tightening Planning Regulations: Under the UK’s statutory framework and local planning policies (including Schedule 3 implementation and CIRIA C753 guidelines), new developments must demonstrate robust surface water management plans before receiving sign-off.
• Local Water Authority Caps: Water undertakers across our operating regions, such as Severn Trent Water, strictly limit discharge rates into public sewers to prevent surcharge during storm events.
• Changing Urban Landscapes: Higher proportions of impermeable surfaces—such as tarmac car parks, commercial yards, and residential driveways—increase rapid runoff, requiring localised storage solutions designed and installed by specialists.

• Capture & Store: During intense rainfall, surface water from roofs, roads, and hardstanding is directed into underground tanks or modular geocellular crates installed during civil earthworks.
• Flow Control: Hydro-brake flow control units or orifice plates regulate the release of water, ensuring discharge into the surrounding watercourse or sewer network does not exceed greenfield runoff rates.
• Pollution Control: Integrated silt traps, catchpits, and oil separators capture debris and hydrocarbons before water leaves the site.

With decades of hands-on experience delivering civil engineering, surfacing, and groundworks solutions throughout the Midlands, JJ Gilleran Ltd acts as a trusted partner for developers, main contractors, and local authorities needing reliable, fully compliant drainage infrastructure.

Our SuDS & Drainage Capabilities:

• Sub-Surface Excavation & Tank Installation: Complete precision excavation, bed preparation, structural backfilling, and installation of modular geocellular crate systems and structural pipe tanks designed to withstand heavy traffic loadings.
• Integrated Surfacing & Drainage: Uniquely positioned to deliver both sub-surface attenuation tanks and surface-level permeable paving, macadam, or asphalt solutions, providing a seamless turnkey groundworks package.
• Separator & Flow Control Integration: Proper placement, levelling, and connection of bypass separators, silt management units, and flow control devices to satisfy Environment Agency and local council requirements.
• Adoption & Regulatory Compliance: Executing all trenching, pipework, and tank installations strictly to local authority standards and water authority specifications for smooth Section 104 adoption.