Drainage Strategy for Planning Applications

Fast & Reliable Reports to Accompany your Planning Submissions

Chartered Drainage Engineers Experts in Drainage Strategies

Our drainage strategy assesses the most sustainable way to discharge water safely whilst complying with the Local Drainage guidelines and the National Planning Policy Framework (NPPF). We also evaluate the management of foul water and determine whether the existing public sewer network requires upgrade.

Our experience allows us to manage water in difficult sites such as flood zone areas, contaminated land, steep or flat slopes or areas located within groundwater protection areas. Our drainage assessments take into consideration the results of the flood risk assessment and drainage strategy guidance.

Our Drainage Strategy Report

Our reports comply with the lead local flood authority standards, the national guidelines, the CIRIA Sustainable Drainage Systems Manual and Sewer for Adoption 8. See below for a list of our pricing:

Drainage Strategy Single House
From £350.00
Building extensions or change of use with less than 100 sqm.
Drainage Strategy Minor Development
From £450.00
Developments of fewer than 9 dwellings or of industrial units smaller than 3000 sqm. 
Drainage Strategy Major Development
From £1,150.00
Developments of industrial/office units bigger than 0.5 Ha or of more than 10 dwellings.
Let's Get Your Project Started

How Do We Work?

urban-water-go-head-flood-risk-drainage
Go Ahead

We will get the available soil information from online databases and (if required) scope the soakaway tests.

urban-water-initial-finding-flood-risk-drainage
48 Hours Later

You receive our drainage layouts based on expected infiltration rates and public sewer capacity.

Submit Our Report

You will be able to utilise our report to register or validate your planning application. We will support you through the planning process.

urban-water-submit-report-flood-risk-drainage
Consultations

We will obtain quotes for soakaways, contact the local water company and agree the drainage design with the lead local flood authority.

Drainage Strategy Fully Compliant with Local and National Standards

Fully Approved by the LLFA
Compliant with the water company standards
Exceedance paths assessed
Maintenance schedule
Water quality assessment
All the network modelled using Windes.

Let's Get Your Project Started

Our Benefits

Time

First report ready in 48hrs. This allows you to register your planning application.

Expertise

We are versatile experts on the creation of drainage design, meeting the local drainage and water company standards.

Success

We have 100% success on obtaining planning using our drainage strategies.

No Hidden Fees

Fixed price for all of our drainage strategies.

Our Sustainable Drainage Strategy Methodology

Our ethos of working in partnerships allows us to incorporate benefits into the design at a very early stage. We have worked with developers, contractors, architects and planning consultants to create sustainable developments in which water plays a fundamental part.

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Obtain project Details

We obtain your development’s drawings and topographical survey levels in mAOD and site location.

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Consult Authorities

We consult the local water company, the lead local drainage authority and the local council and obtain their records to give the development more certainty on the approval.

Urban-water-flood-risk-drainage-design
Scope Investigations

We scope the soakaways. When required, we obtain quotes from our recommended contractors.

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Design and Model

Our designs reflect the most suitable and sustainable drainage system for the soil type, and the quantity and quality of water.  

We are proactive engineers who have an in-depth understand of the need for efficient and sustainable drainage solution within developments. As drainage strategy consultants we create long standing partnerships with architects and developers.

Let's Get Your Project Started

Other Services

Flood Risk Assessment
Our reliable flood risk assessments aid the progress of your planning application. 
Foul Water Drainage Design
Our drainage designs are fully adoptable by water companies and are in compliance with building regulations. 
Sustainable Drainage System
Our detailed sustainable drainage designs are fully adoptable and approved by the council. 
Climate Change Adaptation
We aim to protect communities by using green infrastructure and nature-based solutions to Zero Carbon. 
Let's Get Your Project Started

Frequently Asked Questions

What is a drainage strategy?

The lead local flood authority requires the provision of a drainage strategy for all major developments in England. The aim of a drainage strategy is to determine the most sustainable way to disperse and discharge water without causing flooding to others and the development. A drainage strategy includes the assessment of the soil conditions, the discharge points and of the suitability of multiple sustainable drainage systems such as swales, ponds, block paving and water butts.

How do you manage a drainage system?

SuDS should be designed according to the following standards:

  • Designed and located to facilitate maintenance.
  • Suitably surfaced access tracks for access to the SuDS.
  • Controls and de-silting features should be easily accessible from the surface.
  • Silt traps should be accessible for manual clearance or suction vehicles.
  • Separator should not require man-entry for inspection or emptying.

The maintenance activities for the Sustainable Drainage Systems (SuDS) are fully paid for by the developer, unless they have been adopted by an statutory authority such as the local council. This adoption can be achieved through the use of the Section 106 agreement/separate agreement with the City, district, town or parish council. As part of this agreement, a service management company or private individual/individuals pay Commuted Sums for maintenance.

Sustainable drainage systems SuDS can also be maintained by the local water company using an adoption process. The sustainable drainage system design must follow the rules given in the Design and Construction Guidance (DCG) document. These rules apply to all water and sewerage companies in England from 1 April 2020.

What is a drainage assessment or SuDS report?

A drainage assessment is a specific requirement set out by the lead local flood authority for all major applications. The Drainage Assessment may be part of the Flood Risk Assessment or vice versa. A drainage assessment includes the best practice design for the safe disposal of surface water run-off and includes information on the detailed design, management and maintenance of surface water management systems.

Are Thames Water responsible for my drains?

It depends. As a rule, a public sewer becomes public when two pipes from different sites/dwelling areas joint into a manhole. If the manholes at which the two pipes join and the pipe downstream is a public sewer then Thames Water is responsible for its maintenance.

Thames Water shares maintenance responsibility of the pipe from the boundary chamber (the last chamber within your property) and the public sewer.

Let's Get Your Project Started

What are surface water drainage systems?

Surface water drainage systems are a group of structures that act to manage and dispose of rainwater falling onto a development. Rainwater is managed as close as possible to the roofs or surface, permitting water to evaporate, retain or soak into the ground. For example, by using green roofs and permeable surfaces that allow infiltration. The extra runoff water can be either discharged using ponds or drained to the nearest watercourse. This extra run-off should be discharged at the same rate and volume or lower as would naturally have occurred prior to development.

In the past (and still today) underground piped systems were used to rapidly divert  and move surface water runoff to local watercourses or the sewer system. This process did not allow for water to soak into the ground and enter the natural water cycle. The use of this system reduces the capacity of the environment to easily recharge the groundwater aquifers, which results in the disruption of base flow in streams and rivers. Moreover underground piped systems moves water faster which can increase the risk of downstream flooding and lead to a deterioration of water quality.

Can Sustainable Drainage Systems (SuDS) be adopted?

Yes. There are four options for developers to adopt and maintain surface water drainage systems SuDS:

  1. The local sewerage undertaker or water company could adopt and maintain all SuDS except permeable surfaces, water butts, green roofs and rainwater gardens.
  2. Adoption could be agreed through a Section 106 (of the Town and Country Planning Act 1990) agreement/separate agreement with the city, district, town or parish council and pay the Commuted Sums for the maintenance.
  3. The developer can set up or use a service management company.
  4. The SuDS can be adopted and maintained by private individuals when the SuDS serve individual properties.
  5. The highways authority can adopt and maintain SuDS that serve only the highway.

The adoption and maintenance of all surface water drainage within a development would have to be discussed and agreed with the local planning authority and the lead local flood authority.

How do sustainable urban drainage systems work?

Sustainable urban drainage systems work by making water closer to people and creating streetscapes where people and communities can interact.

The SuDS in urban environments also work by achieving the principles of controlling water volumes, reducing temperatures of surfaces, and making stable urban environments that are more resistant to drought and flooding.

To achieve these principles, places where water interaction is possible should be introduced. For example: green walls, rainwater gardens, street water gardens, reflective ponds, water playscapes and plant drills. 

Single House

Drainage Strategy Single House

Key Benefits:

  • The drainage strategy will inform the flood risk assessment
  • Assessment of available geological records or site investigation if available
  • Obtain and review sewer plans
  • Evaluate potential use of suds applicable to site
  • Determine climate change allowances
  • Undertake basic hydraulic modelling of foul and surface water
  • Calculate storage volumes to comply with suds guidance
  • Indicate discharge points and rates for foul water
  • Indicate applicable suds and volume distribution at a principle level
  • Provide single sketch concept of the drainage strategy
  • Allows for one set of consolidated comments / amendments following first issue of report

What we need from you:

  • Site address
  • Site Layout
  • Topographical survey

Minor Development

Drainage Strategy Minor Development

Key Benefits:

  • The drainage strategy will inform the flood risk assessment
  • Assessment of available geological records or site investigation if available
  • Obtain and review sewer plans
  • Evaluate potential use of suds applicable to site
  • Determine climate change allowances
  • Undertake basic hydraulic modelling of foul and surface water
  • Calculate storage volumes to comply with suds guidance
  • Indicate discharge points and rates for foul water
  • Indicate applicable suds and volume distribution at a principle level
  • Provide single sketch concept of the drainage strategy
  • Allows for one set of consolidated comments / amendments following first issue of report

What we need from you:

  • Site address
  • Site Layout
  • Topographical survey

Major Development

Drainage Strategy Major Development

Key Benefits:

  • The drainage strategy will inform the flood risk assessment
  • Assessment of available geological records or site investigation if available
  • Obtain and review sewer plans
  • Evaluate potential use of suds applicable to site
  • Determine climate change allowances
  • Undertake basic hydraulic modelling of foul and surface water
  • Calculate storage volumes to comply with suds guidance
  • Indicate discharge points and rates for foul water
  • Indicate applicable suds and volume distribution at a principle level
  • Provide single sketch concept of the drainage strategy
  • Allows for one set of consolidated comments / amendments following first issue of report

What we need from you:

  • Site address
  • Site Layout
  • Topographical survey

Sequential Test – District

Sequential Test City District - Urban Water

Our Benefits:

  • Immediate communication with council to determine study area
  • Report in accordance with the local guidelines
  • Assess multiple resources of planning information as per agreed with the council
  • Give preliminary advice on potential sites
  • Recommend appropriate site for assessment
  • Allows for one set of consolidated comments/amendments following the first issue of the report 

What we need from you:

  • Site Address
  • Development Plans
  • Local Planner Contact Details

Single House

Sustainable Drainage Systems Single House

Key Benefits:

  • Design compliant with Building Regs and local water company
  • Scope of site investigations
  • Capacity Assessments from Water Companies
  • Undertake Detailed Hydraulic Modelling
  • Clear Planning Conditions
  • Produce Construction Drawings
  • Providing drawings in .pdf

What we need from you:

  • Site address
  • Site Layout
  • Topographical survey

Minor Development

Flood Risk Assessment Single House

Key Benefits:

  • First draft in 48 hours with the final report in 20 days (dependent on ea information)
  • Report in accordance with the environment agency and with national policy planning framework
  • Allows for one set of consolidated comments/amendments following the first issue of the report

What we need from you:

  • Site address
  • Development plans
  • Topographical ground levels

Major Development

Flood-Risk-assessment-Major-Development

Key Benefits:

  • First draft in 48 hours with the final report in 20 days (dependent on ea information)
  • Report in accordance with the environment agency and with national policy planning framework
  • Allows for one set of consolidated comments/amendments following the first issue of the report

What we need from you:

  • Site address
  • Development plans
  • Topographical ground levels

Strategic Development

Flood Risk Assessment Strategic Development

Key Benefits:

  • First draft in 48 hours with the final report in 20 days (dependent on ea information)
  • Report in accordance with the environment agency and with national policy planning framework
  • Allows for one set of consolidated comments/amendments following the first issue of the report

What we need from you:

  • Site address
  • Development plans
  • Topographical ground levels

Single House

Foul Drainage Design Single House

Key Benefits:

  • Design compliant with Building Regs and local water company
  • Scope of site investigations
  • Capacity Assessments from Water Companies
  • Undertake Hydraulic Modelling
  • Treatment Plant Sizing
  • Drainage Field Calculations
  • Providing design in .pdf
  • Clear Planning Conditions
  • Produce Construction Drawings

What we need from you:

  • Site address
  • Site Layout
  • Topographical survey

Major Development

Foul Drainage Design Major Development

Key Benefits:

  • Design compliant with Building Regs and local water company
  • Scope of site investigations
  • Capacity Assessments from Water Companies
  • Undertake Hydraulic Modelling
  • Pumping Station Calculations
  • Rising Main Design
  • Provide design in .pdf and .dwg
  • Clear Planning Conditions
  • Produce Construction Drawings

What we need from you:

  • Site address
  • Site Layout
  • Topographical survey

Minor Development

Foul Drainage Design Minor Development

Key Benefits:

  • Design compliant with Building Regs and local water company
  • Scope of site investigations
  • Capacity Assessments from Water Companies
  • Undertake Hydraulic Modelling
  • Pumping Station Calculations
  • Rising Main Design
  • Providing design in .pdf and .dwg
  • Clear Planning Conditions
  • Produce Construction Drawings

What we need from you:

  • Site address
  • Site Layout
  • Topographical survey

Minor Development

Sustainable Drainage Minor Development

Key Benefits:

  • Design compliant with Building Regs and local water company
  • Scope of site investigations
  • Capacity Assessments from Water Companies
  • Undertake Detailed Hydraulic Modelling
  • Clear Planning Conditions
  • Produce Construction Drawings
  • Providing drawings in .pdf and .dwg

What we need from you:

  • Site address
  • Site Layout
  • Topographical survey

Sequential Test – City

Sequential Test City Borough - Urban Water

Our Benefits:

  • Immediate communication with council to determine study area
  • Report in accordance with the local guidelines
  • Assess multiple resources of planning information as per agreed with the council
  • Give preliminary advice on potential sites
  • Recommend appropriate site for assessment
  • Allows for one set of consolidated comments/amendments following the first issue of the report 

What we need from you:

  • Site Address
  • Development Plans
  • Local Planner Contact Details

Major Development

Sustainable Drainage Major Development

Key Benefits:

  • Design compliant with Building Regs and local water company
  • Scope of site investigations
  • Capacity Assessments from Water Companies
  • Undertake Detailed Hydraulic Modelling
  • Clear Planning Conditions
  • Produce Construction Drawings
  • Providing drawings in .pdf and .dwg

What we need from you:

  • Site address
  • Site Layout
  • Topographical survey

Zero Carbon Design

Zero Carbon - Climate Change Adaptation

Key Benefits:

  • Complete Cycle Assessment
  • Early Design Optimization
  • Embodied Carbon Calculation
  • Circularity Assessment
  • Carbon Benchmarking
  • Our calculations are based on the LCA standards (CEN/TC350, ISO 218930)
  • It follows the RICS building stages
  • All CO2 values taken from the verified EPD database
  • Compliant with BREEAM UK and CEEQUAL Standards

What we need from you:

  • External Work Layout
  • Initial Drainage Design
  • Site Layouts

Zero Carbon Design

Nature-Based-min.jpg

Key Benefits:

  • Tackle Climate and Nature Crises in Master Planning
  • Example of Using Nature-Based Solutions around the world
  • Utilize the Government’s Research to identify area in which Local and Regional Nature-Based Solutions can be implemented.

Urban Areas

Hydraulic River Modelling - Urban Water

Our Benefits:

  • Models fully approved by the Environment Agency
  • Obtain LIDAR data
  • Produce Hydrological and hydraulic assessment
  • Model Climate Change
  • Site Visit
  • Scope Topographical and measurement survey

What we need from you:

  • Site Location Plans
  • Topographical survey of the site
  • All correspondence with the Environment Agency

Rural Areas

Hydraulic Modelling of River Flow

Our Benefits:

  • Models fully approved by the Environment Agency
  • Obtain LIDAR data
  • Produce Hydrological and hydraulic assessment
  • Model Climate Change
  • Site Visit
  • Scope Topographical and measurement survey

What we need from you:

  • Site Location Plans
  • Topographical survey of the site
  • All correspondence with the Environment Agency

Exception Registration

Flood Risk Activity Permit Exception Application - Urban Water

Our Benefits:

  • Fast assessment on the required exception application
  • Follow up on the Environment Agency
  • Review of your design
  • Review of the contractor’s method statement
  • Assess  the environmental risk for the site

What we need from you:

  • All detailed drawings
  • RAMS
  • Flood Risk Assessment
  • Construction Phase Plan

Standard Rules Permit

Flood Risk Activity Permit Standard Application - Urban Water

Our Benefits:

  • Fast assessment on the required exception application
  • Follow up on the Environment Agency
  • Review of your design
  • Review of the contractor’s method statement
  • Assess  the environmental risk for the site

What we need from you:

  • All detailed drawings
  • RAMS
  • Flood Risk Assessment
  • Construction Phase Plan

Bespoke Permit

Flood Risk Activity Permit Bespoke Application - Urban Water

Our Benefits:

  • Fast assessment on the required exception application
  • Follow up on the Environment Agency
  • Review of your design
  • Review of the contractor’s method statement
  • Assess  the environmental risk for the site

What we need from you:

  • All detailed drawings
  • RAMS
  • Flood Risk Assessment
  • Construction Phase Plan

Sequential Test – Village

Sequential Test Village- Urban Water

Our Benefits:

  • Immediate communication with council to determine study area
  • Report in accordance with the local guidelines
  • Assess multiple resources of planning information as per agreed with the council
  • Give preliminary advice on potential sites
  • Recommend appropriate site for assessment
  • Allows for one set of consolidated comments/amendments following the first issue of the report 

What we need from you:

  • Site Address
  • Development Plans
  • Local Planner Contact Details

Sequential Test – Town

Sequential Test Town - Urban Water

Our Benefits:

  • Immediate communication with council to determine study area
  • Report in accordance with the local guidelines
  • Assess multiple resources of planning information as per agreed with the council
  • Give preliminary advice on potential sites
  • Recommend appropriate site for assessment
  • Allows for one set of consolidated comments/amendments following the first issue of the report 

What we need from you:

  • Site Address
  • Development Plans
  • Local Planner Contact Details

Extensions

Flood Risk Assessment Single House

Key Benefits:

  • First draft in 48 hours with the final report in 20 days (dependent on ea information)
  • Report in accordance with the environment agency and with national policy planning framework
  • Allows for one set of consolidated comments/amendments following the first issue of the report

What we need from you:

  • Site address
  • Development plans
  • Topographical ground levels