A company that damaged a Newater main and wasted enough water to fill three Olympic-sized swimming pools has been ordered to pay a fine of $50,000.
Soil Investigation (SIPL), which had used a drill to test the soil during site investigation works, was convicted under the Public Utilities Act after a seven-day trial that ended last month.
The incident happened during soil drilling works at the Pioneer Road site on March 16, 2015.
District Judge Ng Peng Hong, in judgment grounds issued last week, said the offence was committed due to the negligence of SIPL and found no grounds to excuse liability.
SIPL was awarded the contract by national water agency PUB to conduct site investigation works for the Deep Tunnel Sewerage System on a stretch of land between Benoi Road and Tuas South.
The firm had subcontracted the work to Geotechnical Instrumentation Services (GIS) when the incident occurred.
In a deal agreed between the two firms, SIPL was responsible for detecting underground services.
PUB legal officer Khong Pui Pui, who was prosecuting, said GIS was subject to SIPL's supervision when the offence was committed - which made SIPL liable, unless the offence was not due to its neglect or done without its consent, based on the PUB Act.
SIPL's defence lawyer Faizal Shah disputed the claims.
When GIS carried out boring works at the site that day, as instructed by SIPL, it found an obstruction at the borehole after drilling at a depth of about 6.5m.
SIPL then looked again at the plan supplied by PUB and other utilities drawings, and instructed GIS to shift about 600mm away from the location, and continue to drill at the "offset location".
GIS complied but when it reached a depth of 6.7m, it again encountered obstruction. Water then gushed out from the borehole and work was stopped.
PUB officers who were called to the scene isolated the affected water main and completed the work of plugging the leak after eight days.
The repair bill came to $122,388, and about 7,491.6 cubic m of water was wasted, noted the court.
The judge found that when SIPL - based on the PUB plan it was supplied with - was not able to detect the water mains shown to be located in the borehole vicinity, it did not follow up by consulting PUB, as required.
The judge said: "This lack of consultation showed an utter lack of reasonable precautions and due diligence on the part of SIPL.
"Moreover, SIPL also did not ascertain the depth of the water mains despite the fact that they had contracted to dig 175 boreholes up to 70m, and were aware of the presence of water mains in the vicinity.
"In the circumstances, I found that SIPL was in breach of its duty and was negligent, particularly in the light of the fact that it was aware of the presence of water mains in the vicinity and had receipt of the dos and don'ts."