Fats, oils and grease have been blamed for clogging arteries, so it's no surprise they can also plug neighborhood sewer lines.

Fats, oils and grease have been blamed for clogging arteries, so it's no surprise they can also plug neighborhood sewer lines.

As a result, local sewer officials are stepping up efforts to enforce grease collection at the major sources in the valley — restaurants, coffee shops and bakeries.

"When I started this I was amazed at how much I found," said Mel Workman, an engineering technology inspector for Rogue Valley Sewer Services.

The grease can stop a drain — and block sewers. About two years ago, a sewer line overflowed onto a field in White City.

"We had lines that were pretty chock full of grease," said Carl Tappert, general manager of Rogue Valley Sewer. "Sewer lines are a lot like an artery."

Sewer agencies have since started programs to enforce the installation and maintenance of grease traps at cooking facilities. They even have an acronym to describe the problem — FOG, which stands for fats, oils and grease.

Medford is going to start its own program shortly based on one developed by Rogue Valley Sewer.

Since it began the program in March 2010, RVS has inspected 235 facilities and noted 178 violations, of which 80 have been corrected.

Central Point had the most violations — 45 — followed by Medford and White City.

At 92 of the cooking facilities, grease traps — required by law — were not found.

Another 72 facilities hadn't correctly maintained the traps.

Another 18 violations were issued for restaurants that cranked up the temperature of their hot water to 140 degrees or higher. The higher temperatures allow the grease to dissolve and flow down the drain, but the grease eventually congeals farther down the system, causing problems for sewer lines.

Thick gobs of fat adhere to pumps and other equipment used along the more than 400 miles of lines in Rogue Valley Sewer's system.

Sewer agencies occasionally use high pressure to clean out sewer lines in problem areas, particularly downstream from major restaurant areas.

The biggest surprise for sewer officials has been coffee shops, which generate a lot of fatty substances from milk products and oily residue from coffee beans.

Tappert said his agency has avoided citing anyone, preferring to educate restaurants and other cooking facilities about the need to install equipment and maintain it properly.

Restaurants generally collect most of the oil from deep fryers, but with so many dishes and cooking utensils to wash, a lot of grease goes down the drain.

Various companies will come out to clean the traps, transporting the waste to rendering plants.

Phil Castro, manager of Sonic Restaurant in Central Point, said his grease interceptor is cleaned every three months. Rogue Valley Sewer conducts occasional inspections.

"They first time they told me, I told my crew how to stay on top of it," Castro said.

On Tuesday, RVS found the grease trap in good working order.

Cory Crebbin, Medford public works director, said the city is going to alert the City Council that it is going to start its own program, though it won't be conducting inspections as aggressively as Rogue Valley Sewer because Crebbin doesn't have the manpower.

He estimates Medford has about 300 facilities that generate enough grease to require a trap. Like Rogue Valley Sewer, he plans to rely on education rather than enforcement to get restaurants to comply.

In one instance, he said, a local bakery had been pouring some "magic dust" down the drain, which is supposed to break up the grease. Emulsifiers are not allowed because they create a problem farther down the drain system, Crebbin said.

The bakery stopped pouring the emulsifier down the drain, but new management came in and a salesman sold them the same magic dust.

"These guys sell them these additives," Crebbin said. "It's not supposed to be in the system."

Crebbin said the city could fine businesses from $100 to $1,000 a day for violations, but he wants to try the educational route first.

For restaurants, the expense to install grease traps can run into the thousands of dollars. Most big chain restaurants have programs in place to deal with the problem.

Clearing sewer lines of grease has been an issue on Central Avenue and on Highway 62, Crebbin said.

But grease isn't the worst issue for sewer lines in Medford.

"Tree roots are a bigger problem," Crebbin said.

Reach reporter Damian Mann at 541-776-4476 or email dmann@mailtribune.com.