RICHMOND -- Thieves across the city are prying free and hauling off metal storm drain grates, costing Richmond thousands of dollars and creating a safety hazard for drivers, bicyclists and pedestrians.

"The city is experiencing a rash of stolen curb inlet plates and storm grates this month that represent a troubling theft trend and a safety issue for residents," Lynne Scarpa, a city environmental manager, wrote in an email to police officials Thursday.

The plates are usually 39-by-26 inches of diamond shape metal, and the grates range widely in size and cover storm drains, which could damage cars or cause serious injury if someone were to fall in. Thefts have spiked.

"We normally replace two metal plates a year," Scarpa wrote. "Last month, 10 plates were replaced ... This month, an additional 24 plates or grates are missing." Thieves can recycle the metal for about $2. Replacement costs the city about $300, police Capt. Mark Gagan said.

More than 80 percent of the missing plates are in the city's southern district.

Gagan issued a departmentwide email for police to keep an eye out.

"This type of theft is usually perpetrated by thieves who fund their drug habits," Gagan said. "As metals get scarce, thieves are looking for anything they can get hold of."

Richmond police ask that residents call 911 if they witness a theft of plates or grates.

Contact Robert Rogers at 510-262-2726 or rrogers@bayareanewsgroup.com and follow Twitter.com/roberthrogers