Application for an estimate for new or replacement water supply

(Offsite water connections)

325050 A-DEVSRV-SN45

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Application for an estimate for a new or replacement water supply.

Southern Water own and maintain the large water mains and smaller communication pipes that run in the public highway. The same is true for the water meter installed at the site boundary. The supply pipe is the section of pipework within the private land and is the customer's responsibility. The picture below illustrates this.

If you are constructing a new building or converting an existing building into multiple units, you will need a new communication pipe(s). Southern Water will not allow you to connect any new supply pipes onto your existing communication pipe due to potential complications with pressure and it not being standard industry practice since 1991.

Pipe Layouts
Communication pipes can be in various configurations depending on your development but our aim is to ensure accurate future billing whilst minimising costs to developers.

If you have a shared communication pipe with your neighbour, and you require an independent supply, you will need to bring a new supply pipe to the boundary of the public highway/verge. Southern Water will estimate for bringing a new communication pipe to meet your supply pipe and installing a meter box to join them.

If you are building semi-detached houses and are able to bring both supply pipes to your boundary together, no further than 300mm apart, then it will be possible for Southern Water to estimate for bringing one 32mm communication pipe to meet your supply pipes and installing a two way manifold and meter box to join them.

If you are building a small block of flats with up to six units, and can bring your supply pipes out together, no further than 700mm apart, then it will be possible for Southern Water to estimate for bringing one 63mm communication pipe to meet your supply pipes and installing a six way manifold and meter box to join them. To mitigate the risk of water theft from unused manifold ports, this option is only available where five or more new supplies are required.

All supply pipes, regardless of layout must be laid either in sand or ducts, at a depth of 750mm. They must take the shortest route from the building to the Southern Water stopcock and avoid crossing any third party land. In addition they must be labelled with the plot number, fitted with an internal stopcock and have the end capped off. All supply pipes must pass an inspection by a Southern Water inspector before any communication pipe works can be planned.

If you are building 5 or more new houses, with a new road serving them, you may need a water main to be extended into your site. This can be priced for under the S41 mains requisition application. If you have any queries please email us a plan to in advance of making your application so we can advise on the best way forward.

Internal Meters
Southern Water only permits internal meters to be installed for blocks of flats. Southern Water will install the meters onto your private pipe work that you, the customer, have prepared in advance. Southern Water can supply the meter carriers (manifolds) for you to install if you request this on your application, or you can source and install your own. They must be installed in lockable cupboards, inside communal entrance halls, or basements. The area must be secure, and accessible via key-code entry pad. The terms and conditions we require developers to comply with is available here

Fire Supplies
If you are planning to install a fire sprinkler system, it is essential the background information notes are read and complied with also

Infrastructure Charges
Southern Water applies these charges in accordance with OFWAT ruling, in order to obtain a contribution towards treatment works upgrades. This is because new water connections place an additional burden on existing water treatment sites to produce the fresh water, and up to 95% of that water will in turn enter the public sewer and require treatment at a sewerage treatment works too.

Southern Water applies VAT to its estimates as instructed by HMRC.

  • New build dwellings i.e. new buildings with 3 or more new external walls and roof, are exempt from paying VAT.
  • Listed buildings with appropriate Listed Building Status are also exempt from VAT
  • Existing buildings that are converted to residential dwellings are required to pay VAT at 5%.
Sizing of pipe
A plumbing consultant or plumber will advise you on what size pipe and flow rate is required to serve your specific development. This service is not offered by Southern Water.

Production of estimates
The Developer Services department that processes these applications is required by OFWAT to produce estimates in 28 days from the receipt of a complete application. If anything is missing from your application and we are unable to process it, it will be deemed incomplete, and we will contact you in writing to request this information. Only once we have received all of the required information will the 28 day countdown start.

To produce the estimate, our surveyor will attend site to assess the road conditions and measure up for your requirements. Following receipt of his report, a detailed estimate will be compiled. Due to the fact that it is impossible to truly know what conditions will be encountered until the works commence, the price you receive is estimated. Should the work turn out to cost less than the given price, then you will receive a refund. Alternatively, should the work cost more, then you will receive an invoice for the outstanding amount.

Commercial Supplies
As of 1st April 2017 customers in England and Wales have had the choice of who they purchase their commercial water from. A list of Market Retailers who provide this service is available here Once we have installed your commercial supply, the retailer you have nominated in the form below, will bill you. If you do not nominate a retailer, we will appoint one on your behalf.

For terms and conditions click here

Please check your site is in the Southern Water supply area:

Description of existing site: *
Does the site have an existing water supply?: *
Description of planned development: *
Please tick and complete the relevant option for your development. These are the only options that we offer.
Would you like our surveyor to meet your site agent when they visit? *
E1. Temporary Building Supply (when no existing supply is present)
E2. Separation of shared supply / Upgrade of existing supply.
E3. Apartments
E4. Sheltered Accommodation
E5. Houses
E6. Commercial/Industrial Units
E7. Other (fire supplies, animal troughs, water fountains, etc)
E8. Total number of connections
E9. Will you be installing a tank and booster system? *

Will the development be connected directly or indirectly to the public sewerage system? *

Water Fitting New Development Previous Development Loading Units
Site Contamination
  • If you are applying for reduced water infrastructure charges via the Target 100 scheme, please upload your supporting documentation from Building Regulations confirming that your internal fittings comply with this.
  • If there was previous water usage on your site during the last 5 years, please upload documentation confirming this.
  • A plan clearly showing the site, the nearest adjacent buildings, roads, and where you the developer, will be bringing your private supply pipe to the boundary of the site
  • If you have commissioned a soil analysis report, please upload here.

  • Site boundary clearly shown
  • Roads clearly shown
  • Adjacent buildings clearly shown
  • Private pipe run to Southern Water network clearly shown
  • Maximum file limit is 50MB
  • Allowed file types are DOCX, DOC, PDF, XLS, XLSX, JPG, JPEG, BMP, PNG, DWG (auto cad), DXF (auto cad), DGN (microstation), PRP (microstation), PRW (microstation)
Warning! File size too big. Maximum file size 50MB.
Service Charge
(20% VAT included)
Contestable /
How is this applied?

Failure to include any of the requested information will be deemed as an incomplete application and may result in this application being delayed/returned. This application DOES NOT mean approval has been granted. No work should commence until written approval has been given by Southern Water.
The contents of the report are for direct use only by the applicant and are to be kept private and confidential. They may only be disclosed to third parties with the written approval of Southern Water. Such third parties to have no subsequent implied or other right to disclose the contents and information to any other parties.
Amount to pay
New or Replacement Water Supply
VAT (20%)
Total Fee
Do you require a VAT receipt?: *
Preferred payment method:
Application number:
Amount to pay: £

Payments can be made directly via BACS transfer to:

Southern Water Services Ltd
Miscellaneous Income Account
HSBC Bank Plc
P O Box 125, 2nd Floor, 62-76 Park Street,
SE1 9DZ, London, England

Sort Code - 40-02-50
Account No - 81426834

(However please ensure that you confirm the application number you are making payment for in the reference line)

Please make cheques payable to Southern Water Services Ltd.
Your printed slip and cheque should then be sent to:

Miscellaneous Income
Southern Water
PO Box 4056
BN13 3XX

Please click on ‘Print Preview’ and confirm your cheque number is on the preview slip.
Please print the slip and attach the cheque after writing the application number on the back in case they are separated.

I confirm that to the best of my knowledege the information contained here is complete and correct