Most of the bursts of underground water main are caused by road opening works directly or indirectly. To avoid inconvenience caused to the public, delay of works and liability for high repair costs, contractors should avoid malpractices and take all necessary precautions to protect water mains.
(1) Check Pipeline Alignment
Before works start, contractor should submit to the Water Supplies Department (WSD) layout plans indicating the extent of works so that existing pipeline alignment near the site can be marked on them. Contractor should check the returned drawings to see if any existing water mains may be affected.
(2) Use Pipe Detector
Before digging trial holes by hand, contractor should make use of pipe detector to ascertain the approximate alignment and depth of underground water mains.
(3) Hand-dug Trial Holes
Ascertain the exact position and depth of water mains by hand-dug trial holes, before using mechanical plants for road breaking and excavation.
(4) Careful Use of Plants
Be careful in operating heavy road breaking and excavation plants to avoid damaging water mains and valves near the work site.
(5) Protect and Support Pipes and Thrust Blocks
Provide adequate support and protection for all exposed water mains, thrust blocks and valves.
(6) WSD Assistance
You may consult the relevant Regional Inspector/Region(Inspection) of WSD for assistance in locating existing water mains and providing adequate cover and support for water mains.
(7) Backfilling
To prevent ground settlement adjacent to or below existing water mains, backfill the excavation with suitable materials in layers with adequate compaction.
(8) Site Supervision
Provide adequate site supervision to ensure that all necessary precautionary measures are taken, and remind workers and staff regularly of the importance of avoiding damage to water mains and the full implications of the damage.
(9) Avoid Excessive Loading on Pipes
DO NOT pass heavy plants over buried water mains when the cover has been reduced by road opening works. This is to prevent possible damage to pipe due to excessive loading.
(10) Avoid Disturbing Thrust Blocks
DO NOT disturb or expose thrust blocks without WSD's agreement.
(11) Do Not Undermine Water Mains
DO NOT undermine water mains when excavating trench alongside or across them to prevent settlement of supporting ground.
(12) Do Not Obstruct Valve and Hydrant Operation
DO NOT stockpile excavated material above valves or adjacent to hydrants to ensure that they can be accessed and operated at all times.
(13) Report Main Burst or Leak
In case of water main burst or leak, please report to WSD immediately. Our emergency team will attend the incident immediately.
2824 5000
(Customer Telephone Enquiry Centre 24-hours Hotline)
Contact telephone numbers of WSD's Inspector/Region(Inspection) during office hours are as follows :
| Region | Contact Tel. No. |
|---|---|
| Hong Kong & Islands | 2880 2536 |
| Kowloon | 2360 6544 |
| New Territories East | 2152 5763 |
| New Territories West | 3701 5088 |
For emergency cases outside office hours in which consultation with WSD is required, contact the WSD Customer Telephone Enquiry Centre 24-hour hotline (Tel. No.: 2824 5000)
