What to look for when Locating Urban Residential Sewers?
In residential properties the sewer usually connects to the cities main sewer system that goes to a waste treatment plant. However, there are usually multiple connection of pipes before it connects to the mains. The size, number and complexity can depend of the outflow needed of the residential property, the more toilets, basins, showers, washing machines and wastewater, the larger the system will be. Examples of residential sewers systems can be from outhouses, granny flats, duplexes/semi detached, single family homes, all the way up to large unit apartments. Every country has trade standards for design and installations, In Australia, this is to comply with AS/NZS 3500: Plumbing and drainage requirements.
What should be located in residential properties?
Visual Inspection of the property will give indication of the system and locations underground, Locating any Inspection Openings, Application Connections (toilets etc), Grease traps, Septic tanks, Overflow Pipes and vents are a great place to start above ground.
TIP: Access Issues and Time Constraints are usually working against you as a utility locator, and requires for a clear scope and ways to problem solve efficiently with effective risk management, intuition and documentation helps.
When above ground has been checked and any Inspection openings, overflow pipes and vents have been located, you can then use your utility locating techniques and tools to locate the underground system.
In extremely rare cases, the plumber has connected a trace wire, but most likely you will be using a trace rod or/and sonde to locate most sewer system pipes as a utility locator. Secondly, You can use Ground penetrating radar (GPR) in favorable ground conditions and environments. Rarely, acoustic techniques and equipment can help that much. Manual Potholing with a shovel or NDD techniques is always recommended to confirm on site marking QLB/QLC/QLD positions.
In some cases the system could have multiple drop pipes, connections, inspection openings, overflows and vents depending on the size, company of installation of the property and additional buildings. One reason for this would be added extensions of construction of buildings on a property with hard to access systems, with additional room for separate lines to mains or septic tanks.
There has been an increase in pressurized sewer mains and sewer systems on hill side properties, they usually have power connection for pumps and cutter/grinders and rare cases solar and battery systems.
Innovation with sewer systems using Ancient Technology Designs.
There are some current constraints of course like space, materials and work involved but a interesting idea non then less. Conservation of energy is important within the context. I think you would need about 25 meters vertical depth to get enough pressure to pump a residential sewer to the main, depending on length and diameter of the pipe etc.
The innovation to come with localized pressurized sewer systems will save energy and maintenance costs. This can be achieved with a resurgence in ancient and past technology such as, wind power dating back to 9th Century BC Persia Sistan Plains, where wind power was used to grind up grain, this can replace current sewer mulching/grinding systems without batteries. Another technology revival will be with the trompe system, first documented back in the early 1900s, Used in silver mines in Cobalt, Ontario. The facility harnessed the power of water to generate compressed air with no moving parts. A trompe is a type of hydraulic air compressor which have no moving parts and uses the energy of falling water to compress air, that can replace current pumps for sewage uphill, through pressurized sewer pipes (PSS). The idea is to use wasted energy of storm water from roofs to produce energy to be converted into pressurized air for pump usage and harnessing the wind to grind materials instead of traditional power. There are Solar and Wind power with battery technology is more complex but offer greater advantages for innovation. ‘Everything should be made as simple as possible, but no simpler‘. Albert Einstein. Note: Another interesting technology is a Ram Pump.
Image of what a residential pressurized sewer and grinder system looks like below.
LOL Found this video after i finished this blog post. I was first introduced to this idea through permaculture seminar.
found here; https://www.youtube.com/watch?v=50fJ8Av_g7Q
Another earlier invention is called a Ram Pump, with storm water and septic tanks for storage and combining water and sewerage pipes this may be done. I think because we use more water then what sewage needs to be pumped, i guess this could work. https://www.youtube.com/watch?v=zFdyqTGx32A
Final Notes; PSS Sewers, and Concrete Easements.
Pressure Sewerage Systems (PSS) are in areas where occupied properties use a pump to move their wastewater from their home or building to a smaller diameter pressure reticulation system usually located in the street.
Sewer Easements, there are two main types of easements to watch out for, Design (Planned) Concrete Easements.
Design or Planned Sewer Easements is a type of sewer easement to be cautious of, planned sewer easements on maps by councils, governments or utility infrastructure owners can be there for future development of upgrading the current system for larger transportation of waste. They can also be there because of overflow standards and other design regulatory reason.
The other is Concrete Easements, these are put in place to keep the concrete structural integrity in place, Concrete is used in residential sewers for drop pipes and to protect and stabilize the sewer pipe with concrete.
Hopefully this is helpful in working on your next sewer job as a professional utility locator. Please feel free to comment, question or share any ideas about this subject. Cheers, David Craig Young.
Some additional resources:
This is not medical advice. This post is inline with covid masks for mandatory guidelines for Australia. For more information on mask guideline for Covid 19 masks for Australia, visit the link...
This information has been created for and applies to Utility Locators and New South Wales Fire Services (NSWFS), Australia. Disclaimer: All efforts have been made to give accurate information, of...