Wastewater Collection System Main Repair By Michael Beadnell, Instructor, Texas Rural Water Association
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ost public works licensed operators don’t have the luxury of sitting in an environment with no risks, and it is up to us to work as safely around the biggest dangers that life throws at us. In my opinion, the field of water and wastewater is by far one of the most dangerous but the most important occupations there is. We are experiencing a change in our lifestyles like we have never seen before. People are asked to stay home to keep from elevating the spread of the Coronavirus. For public works employees throughout the state, it has been a challenge to keep up with the growing needs of a community staying at home. America works for a living. We determine our peak demands when citizens are waking up, having lunch and before going to bed. If the majority of our customers are at home 24/7, this requires recalculating. As water and wastewater operators, it is our responsibility to provide potable water, water that has a chlorine residual, has been tested and is safe to drink, and also to stabilize unstable organics to protect public health. The biochemical oxygen demands, total suspended solids, bacteriological samples and every other state and federal compliance regulation don’t go away in a pandemic. On the wastewater side, one of the most difficult emergency call outs is one where there is nothing you can do but to excavate. Customers sometimes flush things that are not compatible to our piping and are not necessarily biodegradable. When excavation is the only option, the first call should be 811. This is the phone number you call before digging to protect yourself and others from unintentionally hitting underground utility lines. Studies show that excavation work is one of the most hazardous types of work done in the construction industry. Accidents in excavation work occur more frequently than accidents in general construction. The primary type of excavation-related work accident is the cave-in. Though these types of accidents are not the most common, when they do occur the related injuries tend to be more serious. Cave-in accidents are much more likely to result in a 26
Quench — 2020 - Issue 3
fatality than other construction-related accidents and account for the largest percentage of preventable injuries. The majority of cave-in fatalities are a result of excavations that either did not have shoring of the walls or the sloping was inadequate to prevent soil from sliding in. Emergency repairs are focused on returning the system to service as soon as possible and are executed to protect public health, which is the operator’s primary duty. Oftentimes the conditions surrounding emergency repairs are not ideal, such as working in the dark, without adequate resources, with fatigue, stress and—most recently — working in the midst of a pandemic. Obviously, permanent, pre-planned and scheduled repairs are preferred to emergency repairs. Most collection system repairs require excavating. Before repairing lines, you need to locate the problem. Televising has proven to be the most efficient and easily reveals the location of the problem. Maps of the collection system are also helpful to locate the line. When all the utility companies have given the ok to dig, the proper personal protective equipment is donned
