Water Management Planning Guidance for Construction Projects

Water Management Planning Guidance for Construction Projects

 

Identify Potential Sources of Water Available

Having identified water needs, it is important to plan for alternative sources within the project, whilst sustaining metered potable supply as back-up supply.

Consider phasing of activities and the use of structures that could be used to:

  • Store (covered tank, positioned in shade and optimal size),
  • Collect (multiple sources and surfaces),
  • Reuse (local tubs and tanks, settlement zone with tap one third up),
  • Save (maintain records of metered or estimated volumes used/reused),

…water during the project.

When considering water use on site, the water hierarchy should always be consulted.

Water Hierarchy

Is the process or activity really necessary?
Is there a cost effective alternative to water?

Eliminate inappropriate use of drinking (potable) water. Can you use rainwater or grey water for the activity/process?

Explore options to improve efficiency. Can fittings or process be updated?

Can water be reused in another process or activity?

Can water be treated/filtered to allow it to be recycled for use elsewhere?

Dispose of excess water legally and responsibly to ensure there is no flooding, pollution or inconvenience to others.

Consider cost and potential health impacts if water is to be reused for domestic purposes, e.g. toilets. More information on this can be found here.

Use the Pre-Start meeting to discuss use and solicit/share water saving ideas from and for all Trades.


Click on the Activities below to find out more.

Water Harvest Tanks (New or Existing)



Supply Water Source Considerations
(Obligatory to maintain operations)
Non Potable Water Harvest tanks (new or existing) Install early for non-potable site use (install draw off pipe or for example connect to toilet flush). Use existing tanks (save from demolition) if available. Record tank volume and/or sub-meter use.


Runoff (Tanks/Storm water ponds - New or Existing)



Supply Water Source Considerations
(Obligatory to maintain operations)
Non Potable Runoff attenuation (tanks/storm water ponds - new or existing) Install early for non-potable site use (Install draw off pipe). Use existing tanks (save from demolition) if available. Record volume and/or sub-meter/estimate use.


Land Drainage Attenuation



Supply Water Source Considerations
(Obligatory to maintain operations)
Non Potable Land Drainage attenuation (discuss risk of increased surface or land drainage issues for the site) Ensure potential land drainage issues resolved at outset of the project to mitigate impact for site. Reinstate or establish land drainage infrastructure or address segregated land drains in early project phase. Map likely pathways for surface water – divert or avoid flow to work area to mitigate wash-out or safety issue and programme delay risks.


Dewater Attenuation from Excavations



Supply Water Source Considerations
(Obligatory to maintain operations)
Non-Potable Dewater attenuation from excavations Reuse (up to 20m3/day without need for abstraction licence) to avoid trade effluent charge and unnecessary surface water loading to wastewater network and treatment systems.


Abstraction License



Supply Water Source Considerations
(Obligatory to maintain operations)
Non-Potable Abstraction licence Sources from river, groundwater, canal.


Storage on site for re-use



Supply Water Source Considerations
(Obligatory to maintain operations)
Re-Use Storage on site for re-use Covered tank, positioned in shade and optimal size, with back-up supply on ballcock to sustain supply if critical to operational need.


Prepare to treat on site for re-use



Supply Water Source Considerations
(Obligatory to maintain operations)
Re-Cycle Prepare to treat on site for re-use Set-up screening, settlement, aeration and retention tanks, with testing regime.


Mains Supply, Hydrant (standpipe) Supply, Bowser or Tankered Supply



Supply Water Source Considerations
(Obligatory to maintain operations)
Potable Mains supply or Hydrant (standpipe) supply or Bowser or Tankered supply Potable supplies identified in activity.


Extend operational use of attenuated sources and rainwater harvesting in life of project and prepare for how these will be decommissioned or managed in transition at handover (e.g. ensure sedimentation is cleared from attenuation prior to tank handover etc.) It is critical that should the feature be retained for the operational phase, the maintenance requirements are clearly communicated.

Ensure fit for use at handover – no residual liability to catchment quality with risk of detrimental impact on the ecological value of watercourse (mitigate siltation) under Water Framework Directive. Non-potable sources are not guaranteed and will need potable water back-up where rainwater and attenuated water supplies are exhausted.