The sewer system, also known as the collections system, includes 2,800 miles of sewer pipe, most of it only eight inches wide. With small pipes like these, DWR employees use a few innovative ways to inspect them and make repairs.

Smoke testing

Smoke testing helps locate faulty pipes, which can allow stormwater or ground water to enter the sanitary sewer system. It also finds illegal connections to the sewer system, like storm drains or roof drains. Stormwater connections to the sewer system cause an unnecessary load on wastewater treatment plants and could potentially cause sanitary sewer backups.

During the test, a non-toxic smoke is forced into the sewer lines in your neighborhood. This smoke leaves no residuals or stains and has no harmful effects on plants or animals. If the smoke is seen coming out of a structure that should not be connected, then the connection can be addressed. Neighborhoods are notified by door hangers at least 24 hours prior to testing.

CCTV

DWR employees use remote control video cameras and other detection tools to assess the condition of our buried pipes to determine when repair, rehabilitation, or replacement is required.

A camera tethered to a cable is lowered into a manhole. Using a large monitor and controls inside of a work truck, the camera can be steered through the sewer system. These cameras can record video footage, take pictures, and even use a zoom lens to look up into sewer laterals. Our specially-trained crews can then use these videos and pictures to determine the condition of the sewer main and its connections. Check out the video at the bottom of this page to see what it’s like to use one of these cameras in the sewer system.

Hydro-jetting

Hydro-jetting is a key part of the sewer maintenance program to keep wastewater flowing through the public sewer system. A jetting unit is mounted on a specialized truck and propels a high-pressure nozzle through the pipes to clear debris, grease, and buildup from the inside of sewer pipes. This helps prevent backups that can lead to overflows.

For most residents, jetting is non-invasive and goes unnoticed. However, on rare occasions, cleaning can possibly affect household plumbing. You might hear noise from sinks, notice toilets gurgling, or in very rare cases, water may splash from toilet bowls. Keep toilet lids closed while work is underway. Odors can also be emitted if water is drawn out of p-traps. If this happens, simply run water in sinks, tubs, and showers to refill the traps. When possible, signs will be placed at neighborhood entrances to notify residents when maintenance is scheduled or occurring nearby.

The network of pipes that carry water from our water production facilities to your faucet is known as the distribution system. DWR maintains the water distribution pipes by providing emergency response to pipe leaks, completing repairs on valves and hydrants, and performing preventative maintenance programs. Our maintenance teams are the first line of defense in maintaining water quality and conserving water. When a water pipe breaks, it is almost impossible to keep delivering water to everyone in the area. However, no matter the time of day, our crews work hard to keep as many people in service as possible and return the other customers back to service as soon as safely possible. DWR has also developed water production and distribution systems with a significant amount of redundancy (duplication of critical components) to ensure the systems are reliable. For example, both raw water intakes can furnish water to the County water filter plants. In the event one water intake fails, the other can provide an adequate supply of raw water to both processing plants to fulfill the needs of our customers.

Unlike the sewer system, our water mains cannot be inspected by CCTV since there is no good way to get the camera into them. So, DWR is looking into other ways of assessing the pipes, including equipment that can measure the pipe wall thickness using electromagnetic fields, and looking for leaks using satellites and methods that were used to look for water on Mars.

To provide a functional and reliable storm sewer system and protect the water quality in our environment, DWR investigates drainage concerns and provides construction improvements for more than 1,700 miles of storm pipes. Stormwater pipes are typically much larger than sewer mains. Unfortunately, they are also impacted directly by the environment and things like branches and leaves can easily find their way into these systems. DWR uses large hoses topped with powerful jet-nozzles to break up the debris into small enough pieces to keep it moving through the system. Clogs and problem areas are usually identified by stormwater manholes backing up during heavy rainfall, which can cause flooding.

DWR crews also maintain the system by removing collected debris from the entrance and outlets of public storm drains. When it is practical to do so, DWR also uses epoxy liners to reinforce pipes that are under stress to avoid digging them up for replacement, which is a significant reduction in cost. It is important to understand that there are many storm drains in the county that are not owned or maintained by DWR. Many pipes, ponds, drainage channels, and creeks are not part of the public storm system and are the responsibility of the property owner instead.