Finding This Sewage Leak Into The French Broad Rivers Wasn’t Easy, But We Got It Done
As I lowered myself into a deep, dark storm drain in the Asheville River Arts District, I asked my coworker “what’s the plan if I can’t climb back out.” She shrugged as I scaled down the drain and reached the concrete creek channel at the bottom.
The infrastructure in the Asheville area is similar to most cities around the country. Rainwater is collected in storm drains, and sewage is piped separately in a maze that snakes under our city and county. The storm drains connect to nearby creeks, and the sewer lines flow down to the Metropolitian Sewer District (MSD) on the banks of the French Broad River, where it is treated and discharged back into the river. Our rivers stay clean of sewage and bacteria when these systems function correctly. However, if a leak forms underground in one of the sewage pipes, that waste will find its way into our waterways.
In order to monitor the health of our waterways, MountainTrue has a team of volunteers that take weekly E. coli data at over 25 locations throughout the French Broad River Watershed. That data is uploaded to the Swim Guide website and app so the public knows how safe it is to swim. When the data from Jean Webb Park, on the French Broad River, kept coming in consistently higher than other locations up and downstream, MountainTrue’s French Broad Riverkeeper team set off to find the source.
A delicious meal at 12 Bones led to a major clue when I spotted a stream behind the restaurant, just upstream of Jean Webb Park, full of algae and smelling like sewage. Water samples confirmed the stream was routinely between four and forty times the safe limit for bacteria pollution.
These samples were taken last November and promptly reported for follow up to MSD, which has proven to be a strong ally in protecting our waterways. They take their responsibility very seriously, and have dramatically reduced the number of leaks and overflows from their system, resulting in a much cleaner French Broad River. Unfortunately, MSD’s initial investigations didn’t reveal any leaks. They dropped dye in multiple sewer lines that flow through the area, but didn’t see the dye turn up in the creek behind 12 Bones.
MSD has another tool in their arsenal, a smoke machine. This machine is attached to a giant fan and blows smoke into the sewer pipes. The idea is that the smoke will come out of the ground or a storm drain if there is a leak in the sewer pipe. The smoke test also failed to definitively locate the leak, so our Riverkeeper team went to every business in the area and flushed dye down their toilets. If there was a leak in one of the pipes that connect the businesses to the main sewer line, then the dye would hopefully show up in the creek. At this point, months had gone by and the river season was fast approaching. We knew that additional tests in the creek were needed to narrow down the source, but the creek and the feeder creeks were almost completely underground.
The North Carolina Department of Environmental Quality (DEQ) was the next stop to helping us locate the leak. DEQ realized access could be gained to the underground creek through some of the storm drains. Additional sampling would hopefully narrow down the location of the source. The samples helped, but we were still left a lot of questions. This is how I ended up 12 feet underground in a stream filled with sewage.
When sampling from an underground creek, we use a pole to lower a sample bottle. As we opened the storm drain and began to lower the bottle down, the end of the pole fell to the bottom of the dark abyss. Cuss words were said, and solutions were tried and failed. Somehow the idea of jumping into a dark hole with no exit plan seemed like the best idea at the time. It took a ripped shirt and a couple dozen cuts before I was able to scramble back out of the drain.
The trip down the drain was eerie and unpleasant, but it led us to devise a sampling plan that could finally isolate all the potential sources of pollution. A return trip was planned that would include a ladder and enough sample bottles to get all the data we needed. First, we placed dye in the three major sewer lines that flow under the area. Then, I climbed into the hole again and tromped down the sewage-filled stream, where I came upon a side channel flowing red from the dye that was dropped in the sewer pipe. Now, we had found a major leak and knew almost the exact location!
We called MSD and they showed up within minutes with 6-8 guys, a camera truck, a pump truck and a lot of fancy equipment. The camera was able to crawl through the sewer line and send video back to the truck. After 200 feet of inspection and no luck finding the leak, I headed back into the hole to double check. We dyed the sewer pipe again, and this time the video found the exact location where the red dye was pouring out of a joint in the pipe.
Anna Alsobrook, our watershed outreach coordinator asked an MSD worker when they thought they could fix the leak. We were expecting a slow bureaucratic timeline, but instead he said, “Right now. There is sewage getting in the creek and we can’t have that.” Sure enough the trucks showed up soon thereafter and they started cutting a giant hole in the road to access the leaking pipe.
The pipe was fixed that same day, and there was a sense of accomplishment. Our hope was that we had fixed the source of the high E. coli pollution just in time for Memorial Day tubing. However, a sample taken the next week showed that this wasn’t the only source of pollution. It took more dye and trips down into the bowels of the city to locate a second smaller source.
Again, MSD showed up within 10 minutes of the call alerting them to the problem, and hundreds of thousands of dollars in equipment was dispatched to locate the exact location of the leak. This leak was smaller and more difficult to find, but was eventually located. Since the leak was small, a patch was proposed, but as the patch was being installed the entire pipe burst. Pump trucks were used to reroute the sewer line while they started to dig up the road. By the time the pipe and road were repaired it was 2 a.m.
This isn’t the first sewer leak and it won’t be the last. Keeping the French Broad River fishable and swimmable requires regular monitoring and investigating when new sources of pollution are detected. That’s why our French Broad Riverkeeper team and volunteer water quality monitors do what they do — to make our river cleaner, safer and more enjoyable for everyone.
Enjoy tubing season!