Around 35 drain covers have been taken from various roads in Livingston in the last two weeks, at a cost to tax payers of around £20,000.
Anyone who witnesses a drain cover being stolen should contact the police on 999, or if you have information on a previous theft, please call 101.
Local residents who notice a drain cover is missing in their area should report it online via Report a Pothole or Other Road Issue by emailing email@example.com with full details or call 01506 280000.
Missing covers also means that an uncovered hole is left on the edge of the road, creating a potential hazard for road users and particularly cyclists and children.
A West Lothian Council spokesperson said: "We would ask the West Lothian public to watch out for any suspicious activity around drain covers in their area.
"Stealing drain covers is both irresponsible and dangerous, creating a hazard for road users and unnecessary costs for the council, at a time when budgets are already under pressure.
"We are replacing the older drain covers with new anti-theft hinged versions to try and prevent future thefts."