Building over or close to a public sewer: Guidance notes

2013

Building Over or close to a public sewer guidance notes

The granting of planning permissions or building regulation approval does not give consent or permission to build over or close to Northumbrian Water assets. Failure to obtain formal approval

from ourselves is illegal and may jeopardise the future sale of your property.

Introduction

Northumbrian water is strongly opposed to construction of any building over, or close to our sewers. This is to protect the sewer and the building from possible damage to each other and to ensure that access to the sewer is not adversely affected. We recognise that under some circumstances, preventing the construction of a building can restrict the improvement of an existing property. In such circumstances and by prior agreement with a property owner, we will accept single story extensions, domestic garages, conservatories and two story extensions to residential properties to be constructed over or close to a sewer, subject to certain conditions, described below

Any pipes in our ownership are in good condition and any necessary repairs can be carried

out by us (at our expense) before the building over takes place

The pipes are properly protected during construction to avoid future maintenance issues for

both our pipes and your property.

A formal building over or money in lieu agreement is in place where needed to show that

you have followed the necessary procedures to protect our drains and your home (and to

protect your interests in any future sales of your property)

Location of sewers

Northumbrian water has over 16,000 kilometres of pubic sewers which have sometimes been laid within boundaries of properties which are shown on our record drawings. In addition to this we recently became responsible for the ownership and maintenance of thousands of kilometres of previously private sewers and lateral drains (pipes outside the property curtilage only serving one unit) which are not currently recorded on our mapping system. Many of these additional pipe lines run at the rear or side of domestic properties in addition to the public sewers and presence of such assets are likely to affect your proposals. If your property was built after July 2011 then your drains may have remained private. When you are requesting a site survey or submitting an application, please indicate the age of your property to allow us to take this into consideration. It is important that you determine the local drainage arrangements on your land and contact us early if you suspect that our drainage pipes may be affected by your proposals. You can find out whether there is a public sewer on your land by visiting any of our offices or the relevant Local Authority offices to view a copy of the public sewer records Alternatively you can request a copy of a plan showing the approximate location of public sewers by contacting our Property Solutions team on 0870 2417408.There is a nominal fee for this service, please refer to our charges scheme. Please note: Recently transferred sewers and drains are not currently marked on our records.

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Build Over options

If there is a sewer within 3 metres of your proposed works you should first consider one of the

following options;

Modify your plans to avoid the sewer, so that the buildings are at least 3 metres away. This

is often the cheapest and easiest option.

If the plans can not be modified, we would usually require the sewer to be diverted. Please

refer to our diversion guidance and application form for further details which can be found

on our website: www.nwl.co.uk/business/dev-sewerage-services.aspx

Under no circumstances will building over be allowed where;

The sewer is a pressurised pumping main

An existing or proposed manhole would be located inside the building.

The development is a new detached development or redevelopment.

The sewer has a formal easement preventing build over.

There is an existing water main.

If having considered the alternatives your only option is to apply to build over, or close to a public

sewer, you should apply using the build over application form.

Build over process

To determine whether or not your proposals may be affected by any of our pipes, please check the

location of your proposed development and the surrounding garden to see if there are any physical

signs of drains or sewers. For instance are there any manhole covers or inspection chambers

visible?

If you are still unsure as to whether you need to submit an application, we are happy for you to

contact us and arrange a site visit by a member of our Clerk of works team. They will try and help

determine the location of any sewers or drains and advise you on what to do next. They will also

attend the site, if your builder discovers any pipe work or manholes after the works have started.

Please contact Northumbrian Water on 0191 4196643 or email buildingover@nwl.co.uk to

arrange this with us.

If an application is required then it is recommended that this is made before you seek planning or

Building Regulation approval and well in advance of works commencing on site.

Once we have received your application we will carry out the following:-

Acknowledge your application in writing and inform you whether your proposal is

acceptable. If your application is not acceptable, we will inform you of the reasons why.

Arrange appointments and attend site meetings where necessary.

Arrange for a Closed Circuit Television Survey (CCTV) survey to be carried out of the

affected sewer.

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Assess your proposals against the criteria contained within Part H4 of the building

Regulations 2010. This will determine whether there is a requirement for a building over or

money in lieu agreement.

Determine any requirements to modify our assets and determine who can carry out the

works.

Provide you with technical information on any protection measures specific to your

proposals.

Liaise with the Local Building control body to keep them updated on the progress of your

application.

CCTV survey

In order to ensure that any pipes in our ownership are in good condition and any necessary repairs can be carried out by us (at our expense) you are required to have a CCTV survey carried out before the building over or close to a pubic sewer takes place.

It is our policy, as recommended in the Building Regulations that we inspect the structural and service condition of the sewers prior to allowing any building to be placed above them. We believe this is essential to ensure that any defects are repaired to protect the long term structural integrity of the proposed building. This also protects you and our other customers served by the sewer from the risk of flooding as a consequence of the sewer failing at a later date directly under the extension.

As the CCTV survey is required as a result of your proposed building works you are required to pay for the survey as part of your application fee. The CCTV survey will normally be carried out within 10 working days of us receiving your application and payment.

Build over agreement or money in lieu

A building over agreement or money in lieu payment will be required where the sewer is either:

Greater than 3 metres deep.

Greater than 225mm diameter in size.

The proposed building is built over more than 6 metres of sewer length.

There is no satisfactory diversion route.

The purpose of a building over agreement is to set out the terms for allowing the building over, the liabilities upon each party with regard to future damage to the building or sewer and agreeing the rights of access to repair the sewer in the event of a collapse. The terms of this agreement can be viewed as quite onerous by some of our customers so we also offer an alternative arrangement in lieu of the legal agreement. In this case customers can pay a sum in lieu of the agreement which insures them against any future failure of the sewer and in this case all repairs to the sewer and consequential damage to the building would be covered by Northumbrian Water.

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In the above circumstances you therefore have two options:

Option 1 - Building over Indemnity Undertaking (Building over agreement) This undertaking provides you and future purchasers of your property reassurance that you have followed all of the correct procedures in order to protect your property and our sewer during your building over process. Such an Undertaking gives Northumbrian Water the option to move all or part of the building, if the sewer requires future repair or replacement, without paying

compensation. Option 2 - Payment in lieu of such an Indemnity Undertaking. Such an Undertaking gives Northumbrian Water the option to move all or part of the building, if the sewer requires future repair or replacement, and Northumbrian Water will fully reinstate the building at our cost. Payment in Lieu is based on the floor area used for building regulation purposes.

The charges associated with entering into a formal building over or money in lieu agreement is additional to the administration charges and given in the charges scheme section of this guidance and the building over application form.

Site survey or inspections

We are happy for you to contact us and arrange a site visit by a member of our Clerk of works

team before submitting an application.

Please contact Northumbrian Water on 0191 4196643 or email buildingover@nwl.co.uk to

arrange this with us.

As part of the application process, it may be necessary for us to carry out further site visits for the following reasons:

To advise your builder on any protection measures specific to your proposals i.e. such as

where sewers cross beneath any load bearing walls.

To determine the requirement of any necessary minor alterations to the existing sewer.

To help us provide you with any estimated costs for minor alterations on the existing sewer

where we have not give permissions for your builder to carry out the works.

To inspect works that have been carried out to protect existing pipe work.

The charges for these site visits are included within the application charge, although there is an additional charge for us to inspect and approve minor alterations to our sewers that we have give your builder permission to carry out.

We recognise that there may be a need for you to request a site survey to try and determine the location of any pipe work on land which you do not own as part of a conveyancing process. We are willing to carry out such a site survey although there will be an additional charge for this service and we will need to be satisfied that you have the consent of the land owner. Please refer to our charges scheme.

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Making minor alterations and new connections Under no circumstances will building over be allowed where an existing or proposed manhole would be located inside the proposed building. Where feasible manholes should be removed and piped through or re-located on the line of the sewer outside the limits of the building. Northumbrian Water are prepared to allow your builder to carry out any necessary minor alterations on plastic manholes and pipes up to 225mm in diameter which are less than 1.05 metre deep. This will be subject to an additional administration and inspection charge to ensure the works meet the required standards. For any minor alterations necessary on our assets which are greater than 225mm in diameter or deeper than 1.05 metres, all works should be carried out by one of Northumbrian Water approved contractors, at your own expense. Costs will be given and agreed with you before work commences. If your proposals require a new connection to a public sewer, you will need to make a separate

application to us. Please refer to our new connection guidance and application form for further

details which can be found on our website:

www.nwl.co.uk/business/dev-sewerage-services.aspx

Foundation Design

Foundations that are located above or within the vicinity of a sewer must be designed to ensure that no loads are imposed on the sewer, and to allow the sewer to be re-laid in the future, without the excavation undermining the building. Where the sewer is to be built over and is passing through the wall of the building, the foundation must bridge the sewer with a suitably designed reinforced lintel. There must be a minimum of 150mm between the underside of the lintel and the sewer, with some form of compressible material placed between the sewer and the lintel. The foundations on either side of the sewer must be constructed to a minimum level of 150mm below the sewer, and the foundation must be adequately separated from the pipe surround/bedding material. Where extensions or buildings are erected wholly to one side of a public sewer the foundation should be placed at an appropriate depth so no load is transferred to the sewer, where the load transference line is assumed to be forty five degrees from the underside of the foundation. When considering the depth of foundation an allowance should be made for the trench width and for any possible future maintenance requirements, which will depend on the size and depth of the sewer. Where a sewer is small diameter and one metre deep or less it should be possible to place the foundation as close to the sewer as practicable by placing a filler board/compressible filler between the foundation and the sewer. Any foundation placed within one metre of a sewer should be placed at least to invert level. Where sewers are greater than 1.80m deep the above will apply but a structurally designed reinforced concrete raft foundation or a piled foundation may also be suitable alternatives. Should you require any further information or assistance relating to foundation designs please

contact us on: 0191 4196643

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Planning Permission and Building Regulations

Please be aware that whilst you may have already obtained planning permissions and may have applied for building regulations approval for your proposed works, you still require our formal approval to carry out works within 3 metres of a public sewer

The legislation that allows us to control the building over or close to a sewer is the Water Industry Act 1991 which imposes a duty on us to maintain all public sewers.

Part H of the Building Regulations 2000 (2002 as amended) sets out the conditions that must be adhered to in order for the Building Control Authority or Approved inspector to allow the construction of a building over or close to public sewer.

We work closely with both the local planning and building control authorities to determine our requirements. As part of our building over process, we will liaise with these to keep them updated on the progress of your application.

Charges

There are charges associated with making an application. These are given in the building over or close to application form and charges scheme. The level of charges will depend on the size of the sewer to be surveyed. There will be additional charges if there is a requirement for a formal building over or money in lieu agreement and/or we have allowed your builder to carry out minor alterations on our existing drainage system.

The application charges include:

Technical vetting and administration

Sewer condition survey (CCTV) and report

A site visit if needed.

Liaising with the Local Authority in line with Building Regulations

A cheque payable to Northumbrian Water Ltd. should be sent with the application to the address given.

Filling in your application form

The applicant’s detail is the address to which you would like us to use for all

communications.

Please let us know whether the best way to contact you is by post or e-mail.

In the ‘other details’ section please confirm details of the existing drainage arrangements if known. This is something that our Clerk of works can help you with during a site survey.

If you are aware of any access issues to your property that may affect our contractors ability to carry out the CCTV survey can you please note these on the form

Using the information in the minor alterations section please indicate if there is a requirement for alterations giving a brief description of what is required and your preference

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to who will carry out this work (Please remember that you only have a choice if the excavation work is no greater than 1.05 metres to the bottom of the manhole or pipe work).

If there is a requirement for a formal building over agreement, please indicate whether you intend to enter into a building over agreement or you would prefer to make a payment of money in lieu of this agreement.

Please indicate the method of payment you have chosen and provide us with your signature.

If you prefer to e-mail your application form to us then please e-mail our New Development team at buildingover@nwl.co.uk and we can send you electronic forms for completion.

How to contact us

Should you require any further information or assistance relating to building over or close to sewers please contact us on: 0191 4196643

You can write to us by post at:

Building Control Team

New Development

Northumbrian Water Limited

Leat House

Pattinson Road

Washington

NE38 8LB

Alternatively you can e-mail us at: buildingover@nwl.co.uk

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Northumbrian Water’s build over or close to public sewer charges scheme

Application Charges

The current charges for a build over or close to a public sewer application are:

Class

I Sewer up to and including 150mm diameter £241.00

II Sewer over 150mm diameter up to and including 375mm diameter £357.00

III Sewers over 375mm diameter £509.00

The application charges include:

Technical vetting and administration.

Sewer condition survey (CCTV) and report.

Attendance on site to agree proposals.

Liaising with the Local Authority in line with Building Regulations.

Agreement Charges (These are in addition to the above) The charge for a building over indemnity undertaking “Building over Agreement” is £340.00 The following charges are made in lieu of entering into a Building over Agreement. The charging bands are based on the floor areas used for building regulation purposes: Building Size (m2) Single Storey Two Storey

Less than 6 m2 £477 £794

6 - 9 m2 £560 £955

10 - 14 m2 £665 £1,113

15 - 19 m2 £763 £1,273

20 - 29 m2 £858 £1,432

30 – 39 m2 £957 £1,592

More than 39 m2

£1,473 £2,397

Site Survey

To determine the location of sewers as part of conveyancing process is £119.00

Inspection charges (This is in addition to the application charge)

The charge for the administration and inspection of minor alterations made by householders own builders £119.00

Initial Location Plan Enquiries (This will not include recently transferred drains and sewers) Copy of the sewerage records single plan A4 £17.40, A3 £24.00, A2 £34.80, A1 £57.60

All the above charges include VAT where applicable.

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Frequently asked questions

Why do I need your approval if I already have planning permission and I have applied for building regulations approval?

We need to approve your proposals if you intend to build over or within 3 metres of a public sewer. This is to protect the sewer and the building from possible damage from each other and to ensure access to the sewer is not adversely affected. The granting of planning permissions or building regulation approval does not replace the requirement for this consent.

What happens if work is carried out without your approval?

It is illegal to undertake works that may damage or interfere with our assets. If we become aware that you have carried out works prior to our approval we can take legal action. Without our approval you may have problems selling your property in the future.

Why do I have to pay? We must recover our costs, to be fair to our existing customers, in dealing with something that an individual customer is proposing.

Why do I have to pay for a CCTV survey of your sewer?

It is important that we inspect the structural and service condition of the sewer prior to allowing any building to be placed above them. We believe this is essential to ensure that any defects are repaired to protect the long term structural integrity of the proposed. As the CCTV survey is required as a result of your proposed building works, you are required to pay for the survey as part of your application fee.

What happens if the CCTV shows that the sewer is damaged?

We will carry out any necessary repairs at our expense prior to allowing any building to be placed above or close to the sewer.

My builder has found a pipe which was not shown on your public sewer records. How do I find out who is responsible for its protection?

In 2011, we became responsible for the ownership and maintenance of thousands of kilometres of formally private sewers and lateral drains in addition to the public sewers which are shown on our record drawings. These are not mapped, so to help everybody understand who is responsible for the pipe, we would carry out a site inspection free of charge. Why can’t my builder carry out minor alterations on your assets greater than 225mm diameter or deeper than 1.05 metres?

It is our preference that all minor alterations are normally carried out by our own contractors to ensure the highest possible standards of construction and health and safety are applied. However, in instances where the sewers are small diameter and at such a shallow depth that we believe it may be appropriate for your own builder to carry out the work under our supervision we will allow you to do so.

Why can’t I build over an existing manhole?

The building regulations does not allow manholes serving two or more properties to be located within buildings. The regulations state that access points should be in places where they are accessible for use in an emergency; such as when sewers may become blocked or collapsed and are causing flooding. They also require that any access points which are removed to allow

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building works must be replaced by a suitable alternative which allows a similar level of access for maintenance purposes.

Can I carry out piling works near sewers?

Where piling works are to be carried out it is important to establish the exact location. We do allow piling works but is recommended that you discuss your proposals with us well in advance of works commencing on site.

Will I have to change my foundation design if located above or near to a sewer?

Foundations must be designed to ensure that no loads are imposed on the sewer and to allow the sewer to be re-laid in the future, without excavation undermining the building.