Assuming we have clear access to the septic tank and there are no maintenance issues with the tank or drain field, we will have your septic tank cleaned in about 45 minutes for 1,000L size tanks and a bit longer for larger tanks. If you leave aside an hour you should be fine.
There are a few things that are difficult to predict that can extend the time we take to complete a job. The foremost amoung these is an excess build up of sludge (solids) in the bottom of the tank. Solids are, of course, more difficult to pump out than liquids and where there is an excess of solids we often need to pump water back into the septic tank in order to make the solids more ‘pumpable’. This flushing exercise may need to be repeated a number of times in bad cases.
Problems with the drain field (indicated by smell or vigorous grass growth around the drains) can extend our stay on site if the client wants us to investigate the cause of the problem. This may mean pumping out the septic tank then inspecting the internal walls, baffles and pipe connections.
We can complete a septic clean while the house is unoccupied (assuming we can access the septic tank), but if you do want to watch the process you should plan to spend about an hour with us.