The sewer network generally doesn’t operate under pressure but the monitoring of the sewer network through flows, manhole levels is an important process of ensuring the network operates effectively and with minimal maintenance.

•  Flow  and CCTV information

Traditionally the sewer pipe condition has been monitored using CCTV and various in line flow meters to determine levels of flow. These processes tend to be batch or off line monitoring and assessed using the software tools and vision from the CCTV.

There is a requirement especially in those areas or catchments that do not meet all the requirements of an asset management model that they are monitored more effectively and again in many cases may not result in new technology but could allow on line and real time assessment of the condition of the sewer.

This concept works as effectively as the water network and by feeding into an Operation Control Centre where the network is being monitored and managed with the maintenance activity clearly focussed on the activity within the sewer.

Many large storm events can cause major sewer issues and the sewer system has been designed to overcome certain storm level activity. With better knowledge and measuring capability the design parameters might be readjusted potentially giving lower construction and operating costs.

• Pipe condition

CCTV has been used as the process to monitor and measure pipe condition but with newer measuring techniques and better pipe integrity measuring systems this might allow more effective pipe condition monitoring. In addition smaller, low powered cameras and better communication techniques may allow in pipe cameras to be maintained indefinitely within the pipe network. This would give on line real time view of the sewer network as well as long term change in pipe and sewer condition.

• Pump station data

A significant component of the sewer network is the sewer pump stations where the gravity sewers are linked to establish the full sewer network. The pump stations are designed and operate to ensure there is no spills from the station but the maintenance regime, the actual design and the criticality of the station require both review and regular understanding of capacity and capability.

Many stations may need generator back up because of their critical nature and the use of SCADA in these environments has been critical to ensure that the pump stations operate in all conditions to monitor the behaviour of the sewer system during those conditions.

• Trade Waste Information

The remaining element of the sewer system is to measure and identify the quality of the sewer or trade waste that is flowing through the sewer network. The type of sewer can impact on the pipe condition, flow conditions under different climate conditions (cold temperatures) and flow rates within the pipe network.

As with water and recycled water the improvements in technology allowing devices to measure on line and in real time can allow better management of the final sewer treatment but also lead to better management of the waste producer further enhancing the proper management of the network.

Recycled Water

The focus on fully understanding water usage and how it applies across the entire landscape has allowed a focus on reducing the overall dependency on potable water for activities that do not necessarily require this level of purity. As this develops further the ability of an intelligent network to monitor and then control some of the water parameters and potentially the water source will allow effective management of the water resources.

Recycled water can come from many different sources with potable water replacement and potential environmental improvements resulting from less  outflow to the environment especially from sewer treatment outflows. The ability to monitor flows and water quality and maintain long term records of this information will become a critical component of the water supply system and the intelligent networks.