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Excavation for Sewer & Drain Line Repair

We Specialize in Sewer & Drain Line excavation for both Commercial and Residential Customers in Central Texas.

Excavation – Tunneling & Trenching

When choosing a plumbing company to perform sewer & drain replacement, a property owners main focus should be the excavation portion of the job. Trenches and tunnels must be excavated to expose the sewer & drain lines for repair. Tunneling beneath a commercial or residential building requires specific procedures and safety standards. It is a complicated process that only a true professional can perform. When we tunnel beneath your foundation, we make sure you are educated and informed every step of the way. We hire top professionals and invest in the best training methods and equipment ensuring that tunneling is achieved safely, promptly and effectively. Our employees hold multiple OSHA certifications and attend safety training workshops regularly.

When choosing a plumbing company, it is important that you ask questions, such as:

  • Are the excavators employees or sub-contractors?

  • Do the excavators follow required OSHA procedures?

  • Do the excavators have OSHA certifications?

  • Are the excavators insured?

  • Will I receive an engineer’s letter from the excavators?

  • Do the excavators have a contractors’ license or contractor registration card?

Tunneling & Backfill

Tunneling is the process of digging a tunnel under a home foundation. Tunnels must be dug by hand and is very labor intensive.  Tunneling requires proper planning (to meet OSHA requirements) and lots of manpower to safely complete the job. Tunneling, drain line replacement and foundation repair are what we do best, they are our specialties. It is important that tunnels are excavated with your foundation in mind as to not compromise the foundations’ integrity. As both a sewer & drain excavation company as well as a foundation repair company, we take the necessary precautions to protect the integrity of your foundation.




Once the tunnel and plumbing repairs have been completed, an independent certified engineer will review the project. The engineer will ensure that the foundation has not been compromised and that all work was performed by industry standards. The engineer will produce a report to be shared with both the city inspectors and homeowner. After passing the engineer and city inspections, we will backfill the excavation and patch all concrete access holes. If contacted, the engineer will discuss the project with property owners and anyone related to the project.


It is extremely important that the backfill does not disturb the “fall” or “pitch” of the lines. If the backfill is performed incorrectly, your lines may become disturbed or compromised. Our backfill will be performed in accordance with the engineer’s requirements and the local municipality. Please remember, backfill must be performed by a professional in accordance with the outlined requirements.  


We approach every job with:

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  • Safety

  • Attention to Detail

  • Clear Communication

  • Excellent Customer Service

  • Superior Workmanship

It is important to note, most plumbing companies, big & small, have very little to no experience with regard to:

  • OSHA Requirements for "Confined Space" (Very Important)

  • Replacing Sewer & Drain Lines Beneath a Foundation

  • Maintaining the Integrity of a Foundation While Excavating

  • Backfilling and The Techniques Associated with The Backfill Process

  • Supervised by an OSHA “Competent Person” (“Competent Person” – OSHA designation)

At CastleRock we strive to work in a safe, clean and efficient manner at all times. The construction of underground tunnels are an essential but dangerous activity. Working under reduced light conditions, difficult or limited access / egress, with the potential for exposure to air contaminants, underground workers face many dangers. To help employers protect the safety and health of underground construction workers, the Occupational Safety and Health Administration (OSHA) has prepared a number of guidance documents, including the underground construction regulations, found in Part 1926, section 800 of Title 29 of the Code of Federal Regulations (29 CFR 1926.800). At CastleRock, we take these guidelines seriously and follow them closely.

Our employees work in teams of two or more and are trained to recognize and respond to hazards associated with tunneling & trenching. The plan of action is tailored to each specific jobsite and includes any unique issues or requirements. CastleRock maintains open lines of communication with its workers at the worksite to ensure a rapid and complete exchange of information concerning events or situations that may impact worker safety. We stress to workers in and around the jobsite that they should not perform an activity they are not comfortable performing.

Our team training is tailored to the types of jobs in which we work.  Specifically, air monitoring, ventilation, illumination, personal protective equipment, emergency procedures and mechanical equipment. If natural ventilation does not provide the necessary air quality, we direct fresh air into our tunnels.

Every jobsite has a "competent person" as defined by 29 CFR 1926.32 (f) who is capable of identifying existing & predictable hazards. The competent person is responsible for crew safety, air monitoring, ground stability and the transport of equipment. The competent person must inspect the roof (slab), face, and walls of the work areas periodically during the day to ensure ground stability. Trenches more than 5 feet in depth must be supported by a trench shield. We place barricades and warning signs around trenches and tunnels to prevent entry into the work space by individuals other than permitted workers.

CastleRock Excavation prices include OSHA approved devices for our workers. Our clients are not required to provide our workers with safety equipment.

Permits & Codes

In addition to plumbing codes, most municipalities have specific guidelines for plumbers and require permits for residential and commercial projects. CastleRock will work with your specific municipality and local inspectors to ensure the project is completed to the municipalities specifications and that the permit has passed all stages and has been closed.

CastleRock’s plumbing license number: M-42049.