Why Does My House Need a Sewer Ejector Pump?

If you are building a new home on a sloping block or putting a granny flat out the back of your existing property, the chances are you are going to need a pumping station to lift the wastewater from the toilet, sinks and shower to the conventional gravity drainage system further up the property. The same applies if you are building a new home and the wet areas or kitchen are lower than the SA Water sewer street connection, otherwise known as the Government Inspection Point.

Why More Adelaide Homes need Sewer Ejector Pumps

What we are seeing today in Adelaide is that with the decrease in vacant land, locations that would once have been deemed unsatisfactory to build upon are now being built upon. Retaining walls, extensive pre-earthworks, steep driveways and pumping systems are being introduced to make a parcel of land usable for residential development.

The initial build costs have skyrocketed, but the location of the build is still close to the Adelaide CBD in desirable suburbs.

Good examples of this can be found in Glenelg, Beaumont, Burnside, Norwood, Medindie and North Adelaide, where houses are being built with garages and habitable basements below the street level to maximise the overall house by using as much of the land's footprint. Access to these can be via stairs or lifts, but unfortunately many of these finished floor levels end up too low for conventional gravity-fed sewer drainage installations.

You will find gravity sewer drainage installed at 1:50 grade via 100mm DWV PVC, but this will end up discharging into the sewer station and will require some form of venting, typically via a 50mm PVC pipe to atmosphere, as these lids for access to the pits are gas-tight to hold offensive smells inside them.

Hybrid Sewer Pumps for Modern Installations

Over time, technology has changed with many things in our lives, and a piece of technology far from many people's minds is the sewage pump. Today we are using a hybrid sewer pump in many of our new pumping station setups and replacement pump jobs. The hybrid submersible sewer pump is able to process solids and grind them up before the liquid waste enters the impeller.

The advantages of this are minimising the risk of impeller jamming, avoiding electrical motor fusion or burnout, maximising flow rate and discharge heights through the pump's impeller, and minimising emergency pump fault call-outs. Many of these systems use cutter or grinder pump technology suited to residential ejector pits.

Although we have touched on hybrid sewer ejector pumps, not all setups have this style of pump, and it is worth noting that no matter what style of pump you have, it is vitally important to carefully watch what is flushed down these plumbing pipelines. Even with the best pumps money can buy, if the wrong thing is washed down the pipes, it could end up jamming the impeller of the submersible pump.

Single Vs Multi-pump Stations

Throughout the many decades of working on all types of pumps across metro Adelaide, rural, coastal and the hills, we have encountered many different types of sewer pump setups. In low-use locations, single pump installations are satisfactory. In larger, high-volume installations, multi-pump installations are used to control volume during peak flow and for backup if one pump were to fail.

Our Pirie Street commercial sewer pump call-out shows what happens when a duty/standby station is left without maintenance: one pump can sit failed for months while the second burns out under continuous load.

Why Chamber Size and Float Setup Matter

The size (volume capacity) of the pumping station itself is also worth noting. You do not want the pump or pumps to short cycle, so sizing the pit is crucial. In low-demand situations, the pit can be smaller as the frequency of use is low, so the pit will take a while to fill up and activate the run float and avoid short cycling.

But in high-demand locations such as commercial buildings and office blocks in the city, we do not want the pumps to short cycle, so a large chamber is installed to handle and store the large volumes of liquid waste and still only pump out on regular occasions, not to have the pump continually in run mode. Short cycling of the pumps will decrease the life of the pump as it is working twice the amount in a shorter period.

The setup of the run and stop floats can also contribute to this, so having these set up at the right levels plays a crucial role in the commissioning of a station.

For a fuller design checklist covering discharge pipe, head pressure, venting and float style, see key components when designing a pumping system. If you are unsure whether you need a sewer pump or a sump pump, read sewer pumps vs sump pumps.

Engage Pump Plumbing Specialists

It is with all these key elements that the engagement of pump plumbing specialists is very important. At Mayfair, we pride ourselves on being able to provide both plumbers and electricians who can undertake the entire project from start to finish without the need to outsource any of our work.

The ability to do this leaves our clients with peace of mind that the task will all be done in a timely, professional manner.

If you require the assistance of a pump specialist in Adelaide, call Mayfair Plumbing any time of day or night - 24 hours, 7 days a week, including public holidays. Call 0429 361 819 or request a quote for sewer ejector pump installation and servicing.