Bromsgrove | Redditch | Wyre Forest
North Worcestershire Water Management
Water Management Advice: For larger applications
Guidance note on the production of a Water Management Statement
What is a Water Management Statement (WMS)?
A WMS is a document which describes all measures that you are intending to install to deal with the water management aspects of your proposed development.
A WMS can consist of anything from a few lines to a few paragraphs, or even a single side of A4. Unlike a Flood Risk Assessment (FRA) a WMS is not a legal requirement. However, it will assist in processing your planning application.
Who should read this?
Anybody who is intending to apply for planning permission where water will be used and / or disposed of.
North Worcestershire Water Management (NWWM) has developed two advice notes, one for household applications and one for larger applications. This one deals with larger applications, defined as any application involving more than one property.
When to submit a WMS?
A WMS can be submitted simultaneously with the planning application or you could also decide to submit it prior to this.
There are no fees associated with the WMS.
Who to submit it to?
You can include your WMS within your planning application when you submit it to the relevant council. Alternatively you can submit it directly to NWWM.
NWWM recommend a WMS to accompany all planning applications where water will be used and/or disposed of. This statement will assist in co-ordinating between regulatory authorities across North Worcestershire in the resolution of water management with the following main aims:
- minimising flood risk;
- managing surface water;
- achieving sustainable drainage principles in new and existing development;
- incorporating appropriate water management techniques into new development;
- ensuring priority is given to the re-use and recycling of water;
- ensuring new development negates any adverse effects on the water cycle, supply and quality;
- establishing the life-long maintenance and management responsibilities for all water management facilities;
- restricting the developed rate of surface water run-off;
- requiring the provision of water harvesting, saving and recycling devices in new development;
- and maximising biodiversity gain from both Sustainable Drainage Systems (SuDS) and open space areas incorporated into new development.
What are Water Management Techniques?
Water Management Techniques aim to prevent run-off as it drains from a site. There are a number of techniques that can be applied to help manage water, as a result of development, including:
- SuDS (Sustainable Drainage Systems), which provide a sustainable solution to help reduce and manage surface water run off, which might otherwise cause flooding, and pollution. These are systems created to receive surface water run-off and provide drainage solutions that mimic natural processes rather than piped solutions(e.g. ponds, wetlands, detention basins, underground storage, swales, filter and infiltration trenches, filter strips and permeable surfaces). The council will require the provision of SuDS techniques in all householder proposals that involve changes to a sites drainage characteristic, in order to minimise the impact of surface water run-off from the site. Details on SuDS techniques can be found in the CIRIA
publication ‘The SUDS Manual (C697)’ available from their website: www.ciria.org. - Rainwater harvesting is described as water collected from roofs and directed to either water butts, above or underground tank(s). This water is then pumped on demand direct to toilets, washing machine and outside taps.
- Greywater recycling is defined as the re-use of water from the bath, shower and wash hand basin. The ideal situation for greywater is in living accommodation where sufficient amounts are generated daily for reuse in toilets, the washing machine and any outside tap.
Requirements for larger applications
| Development type | Measures to consider | Reason | Water Management Structure to produce |
|---|---|---|---|
| Two to ten house development | Rainwater harvesting to capture roof water discharge for non-drinkable water use; water butts on downpipes; low water use appliances (dual flush toilets, permeable paving etc.); water attenuation measures (swales, detention & retention basins);multi-functional spaces (open park spaces). | To reduce surface water discharge; to encourage surface water recycling; to reduce fresh water usage; to control the flow of water during storm events; to create amenity with floodplain space when required. | One to two sides of A4 would normally provide enough detail for a larger development, such as 2–10 houses. |
| 11 or more houses | Rainwater harvesting to capture roof water discharge for non-drinkable water use; water butts on downpipes; low water use appliances (dual flush toilets, permeable paving etc.), water attenuation measures(swales, detention and retention basins, storm water attenuation tanks if necessary), multi-functional spaces (open park spaces). | To reduce surface water discharge; to encourage surface water recycling; to reduce fresh water usage; to control the flow of water during storm events; to create amenity with floodplain space when required. | A detailed document of two sides+ of A4 would provide enough detail for a larger development, such as 11+ houses. |
Other requirements
Consent
Consent may be required for works, irrespective of whether temporary or permanent, where the flow of a watercourse is likely to be affected. The Environment Agency provides consent for works in a Main River, and NWWM provide consent for works in an Ordinary Watercourse. The process takes 8 weeks at a fee of £50.The consenting authority will screen the application to determine if a Water Framework Directive assessment (or other such assessment) is required. Enforcement action may be taken for any damaging or potentially damaging works which have been undertaken either without consent or are in contravention to an issued consent.
A Site-Specific Flood Risk Assessment (FRA)
A site-specific flood risk assessment will also be required for planning applications relating to areas of flood risk. This will depend on the size, type and location of the development. The objectives of a FRA are to determine whether a proposed development is likely to be affected by current or future flooding from any source; whether it will increase flood risk elsewhere; whether the measures proposed to deal with these effects and risks are appropriate; and whether the development will be safe. FRA’s come in three levels depending on the scale and nature of the development (Level 1 –Screening study, Level 2 –Scoping study & Level 3 –Detailed study). For more information on FRA’s please visit The Environment Agency or refer to The National Planning Policy Framework document.
A checklist for larger planning applications
Before submitting the WMS you might want to read through this checklist to assure yourself that all water management aspects relevant to your development have been adequately covered.
- Have you included details about the level of flood risk to your proposed development & included a FRA if required?
- Have you included details to demonstrate that your proposed development will not create or exacerbate flooding on or off site?
- Have you included details about how you are proposing to dispose of foul and surface water?
- Have you introduced SuDS techniques where possible? (If it has not been possible to drain surface water through the ground, it is necessary to look at the potential possibility of draining it to a watercourse or a surface water sewer).
- If a soakaway is a considered measure, proof of a porosity test with accompanying calculations to prove its capability will be required.
- Does the design incorporate facilities to collect, store and use rainwater and / or greywater?
- Do your landscaping schemes and planting design plans for the site minimise the need for watering?
- Has the effect of the development on the quality and quantity of run-off from the site been considered?
If there is any aspect of this that you are unsure with please do not hesitate to contact North Worcestershire Water Management for further advice and information and we will respond within 21 days. We do not charge for pre-application advice or consultation on the water management aspect.
Email: enquiries@nwwm.org.uk
Telephone: 01562 732191 (Monday to Friday, 9am - 5pm)