Drainage Design

Technical Precision for Adoptable Sewers, Private Infrastructure, and Strategic Diversions

A well-designed drainage system is the invisible backbone of any successful development. At Ellipsis Consulting Eningeers Ltd, we provide the detailed hydraulic modelling and engineering drawings required to move your project from a planning concept to a physical reality.

From large-scale adoptable sewer networks to complex private basement drainage and strategic sewer diversions, our designs ensure water is managed safely, efficiently, and in full accordance with the latest Water Industry Act and Building Regulations.

Our Core Drainage Engineering Services

We provide a comprehensive approach, ensuring that your site’s internal drainage works seamlessly with the public network.

Adoptable Sewers & Strategic Infrastructure

If you require a water company (e.g., Thames Water, Anglian Water) to take over long-term maintenance or need to alter the existing public network, we manage the full technical process:

• Section 104 (S104) Agreements: Designing new gravity sewers, pumping stations, and SuDS for formal adoption.

• Section 185 (S185) Sewer Diversions: Is an existing public sewer blocking your building footprint? We design diverted routes that maintain network integrity while freeing up your developable land.

• Section 98 (S98) Sewer Requisitions: If your site lacks a direct connection, we design the "off-site" infrastructure required to bring a public sewer to your boundary.

• Section 106 (S106) Connections: We provide the detailed manhole and pipe designs required to secure formal approval for new connections into the existing public main.

Private & Plot Drainage (Part H Building Regs)

For infrastructure that will remain under private ownership—such as commercial yards or individual building plots—we provide high-performance, cost-effective solutions:

• Foul Drainage Design: Calculating peak flow loads to ensure pipe sizes are optimised for residential or commercial occupants.

• Surface Water Management: Designing the "on-plot" pipes, gullies, and channel drains that feed into your wider SuDS strategy.

• Pumping Station Design: Expert specification and sizing for sites where gravity-fed drainage is not an option.

Advanced Technical Capabilities

We use industry-leading software (including MicroDrainage and Causeway Flow) to produce data-driven designs:

• Hydraulic Modelling: Simulating storm events to ensure your pipes handle a 1-in-100-year rainfall event plus climate change allowances.

• Conflict Detection: Coordinating with our Highways and Utilities teams to ensure drainage runs do not clash with gas, electric, or road foundations.

• Codes for Adoption: Every adoptable design is fully compliant with the "Design and Construction Guidance" (DCG) to ensure a smooth approval process.

Sustainable Integration (SuDS Design)

Drainage design is no longer just about pipes. We integrate "soft" engineering into our technical layouts:

• Attenuation & Flow Control: Sizing underground storage tanks or crates and specifying Hydro-Brakes to strictly limit discharge rates.

• Headwall & Outfall Design: Engineering the safe discharge points into local watercourses or public sewers.

Why Work With Our Engineers?

• Unlock "Unbuildable" Land: Our S185 diversion expertise allows you to maximise site potential by moving restrictive infrastructure.

• Reduced Construction Costs: We avoid over-engineering, saving you money on materials and excavation through precise calculations.

• Liaison-Led Approvals: We handle the technical "back-and-forth" with Water Authorities and Building Control on your behalf.

Let’s Engineer Your System

From initial S185 feasibility to final S104 technical approval, our team is ready to deliver.