PORTLAND – For the first half hour or so, I didn’t think working at a wastewater treatment facility was as dirty as it sounded.

Sure, the smell was bad. In fact, it was almost nauseating in certain parts of the Portland Water District’s giant East End Wastewater Treatment Facility near East End Beach.

But as I followed Rocco Botto around, I found that a lot of his job consisted of checking on things to make sure everything was running smoothly. Pretty clean stuff.

We peeked into little tanks to make sure wastewater samples had been collected properly. We put our hands on pumps to make sure they were running. We went inside rooms to check tanks for leaks.

And we walked a lot. Much of the plant is underground, with a quarter-mile-long tunnel connecting the various working areas.

But then we got to an area labeled “Return Activated Sludge Pumps.”

Botto told me that once a week, these pumps had to be opened up.

And they had to be cleaned out.

“You get sticks, baby wipes — anything people flush down the toilet can end up in here,” said Botto, 61, a senior wastewater operator.

I was hoping Botto would hand me an extremely long gadget to clean out the pumps. Instead, he grabbed a pair of black rubber gloves that were so long, they reached up to my shoulder.

“I’ll go upstairs and turn the pump off before you stick your arm in there,” he said.

Uh, thanks.

PADLOCK THOSE PUMPS

Once the pump was off, I stuck my arm all the way into an opening that was only about a foot in diameter. Botto told me to feel around the pump’s impeller blades to see what I could find. I poked around in the murky water and couldn’t find anything of substance other than the water itself. Then Botto stuck his arm in to make sure I hadn’t missed anything. I hadn’t.

Later, Botto showed me a room in an upper level where he had padlocked the controls to the pump. Anytime anyone at the plant works on a pump, the controls have to be padlocked so the pump isn’t accidentally restarted.

Botto’s job has a lot of specific duties — routine maintenance, checking for leaks and problems, working the computer, doing some lab tests, draining and hosing down tanks — but broadly speaking, his job is to keep the plant running. Wastewater from toilets all over Greater Portland comes to this plant to get clean.

There is a lot of science to Botto’s job, too. He explained that the wastewater comes through an aeration tank, where air and bacteria and other microorganisms help break it down and get rid of harmful matter. Then it goes to a sedimentation tank — a giant domed structure that looks like a small covered sports stadium — where sludge settles to the bottom.

At one point we were inside one of these domed tanks, where I used a 10-foot-long hollow pole to measure the sludge, one of Botto’s routine checks on his daily checklist. Standing on a metal bridge over the water, I dropped the pole in and watched it sink. It was attached to a rope and eventually found bottom. I then pulled it up and saw that some of the hollow pole was filled with sludge and the rest was water.

“That’s about a foot of sludge. That’s probably just where it should be,” Botto said approvingly.

After it settles, the sludge gets treated some more, is eventually pressed into a fairly solid form, and then trucked to a landfill. The water part of the wastewater is eventually treated with a disinfectant. When it’s 90 percent clean, it’s released into Casco Bay, about a mile offshore.

There are more steps than I described, but I don’t pretend to understand them. Botto has been working for the water district for more than 30 years, and had to take a test to get his operator’s license.

BIG POOLS, NOT FOR SWIMMING

Before we opened that pump that I stuck my arm into, Botto and I had to open and shut valves by hand. He opened some with a wrench as big as a snow shovel. One valve that I opened was 10 feet over my head, and I had to open it by yanking on a chain repeatedly for two or three minutes to make it turn.

Sometimes, Botto’s job takes him outside for several hours. When I was with him last Tuesday, the temperature was about 20 degrees and the wind blowing from the nearby ocean was stiff.

We negotiated a series of walkways over a number of outdoor detention tanks the size of several Olympic swimming pools, where the water sits for a while before being pumped into the ocean.

There was a life ring attached to a railing on one walkway, but the current of the water in these giant waterways was such that I couldn’t imagine having much time to grab onto anything.

Botto said that later on in the day, one of these pool-like structures had to be drained and someone would have to stand out here in the cold for several hours to hose it down so that built-up sediment could be washed away.

Luckily, we didn’t have time to do that. Instead, we headed back into the warmth of the plant and finished our rounds by checking into a room labeled “sludge cake garage.”

There, we watched sludge the consistency of clay being dropped from a pipe into a large steel receptacle. After lots of scientifically proven processes, the sludge was now dry enough and solid enough to be trucked to a landfill, Botto told me.

“I don’t think people understand how much science goes into this,” said Botto.

I’m sure he’s right. But I’m not sure many people would be willing to get close enough to find out.

Staff Writer Ray Routhier can be contacted at 791-6454 or at:

rrouthier@pressherald.com