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Impact Assessments

Water Impact Assessment

Water Impact Assessment


The Water Impact Assessment application is a referral application following the Pre-Development Enquiry process and needs to be submitted as soon as is practicable and prior to any formal planning submission. 

Failure to complete all sections will result in the return of your application. Please refer to our guidance details below before completing your application.

Northern Ireland Water provides a Water Impact Assessment service to assist developers in identifying any possible network reinforcements and/or constraints that may be associated with servicing a development site in terms of water infrastructure. The Impact Assessment, which involves hydraulic assessment or network modelling, can assist developers in understanding the potential costs and timescales involved in servicing a site prior to land acquisition or in advance of the submission of a planning application. The results of the Water Impact Assessment are for information only and should not be regarded as an approval or rejection of your proposals. 

The Water Impact Assessment is a more in-depth service than a Pre-Development Enquiry. It aims to identify the most appropriate point of connection and the indicative hydraulic assessment for servicing the site (as recommended in Pre Development Enquiry response).

Should you wish to take advantage of this service, please fully complete the Water Impact Assessment application form (W-IA)and forward with the appropriate fee to the address below.

NI Water will endeavour to provide you with the recommendations from the Water Impact Assessment report within 65 working days of receipt of a complete application provided there are no constraints. If NI Water are unable to do this you will be contacted and given the reason why with amended timeframe.

NI Water will inform the developer if there is insufficient capacity within the water network to accept the new development, advise on what reinforcement of the network is required (if applicable) and next steps. (Where a developer is advised to submit an external watermain requisition application they will be advised of costs and any required contribution as part of conditional response.)


  • It is important in the application that the applicant ensures that the Peak Flow Rate (l/s) and average ‘Continuous Flow Rate’ (l/s) requested are reflective and realistic.
  • Please provide supporting calculations/information on how the Peak Flow Rate (l/s) and average ‘Continuous Flow Rate’ (l/s) have been arrived at.

Fire Protection Requirements

  • Please note that NI Water does not have a duty to provide infrastructure specific to firefighting, i.e. hydrants or additional mains capacity.

Water Loading Units Table

  • Please ensure this is fully populated for all proposed Commercial and Industrial development.

Returning completed forms

Please return completed form(s) and appropriate fees to:

Developer Services - Servicing Team

Northern Ireland Water

Ballykeel Office

188 Larne Road

Ballykeel, Ballymena

Co Antrim BT42 3HA

Telephone:03457 44 00 88

Email: developerservices[AT]niwater[DOT]com

For more information on how NI Water lawfully processes personal data please refer to our Privacy Notice:

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