Belgian wastewater utility Riobra has been utilizing the powerful interconnectivity of MWH Soft’s InfoNet solution to enable it to plan, construct, renovate and maintain a number of key Flemish wastewater networks.
Riobra is an inter-municipal company, responsible for the sewer systems of 24 Flemish municipalities in Belgium. The company’s main tasks also include creating new house connections and maintaining its networks to ensure they function well.
The company’s operations also encompass combined, storm and foul water sewers, pumping stations, small-scale wastewater treatment works and stormwater retention basins.
Central to Riobra’s approach are its GIS system and an administrative database, iSeries. The company’s goal is to keep these up-to-date so that it can provide information to its customers - its clients and the inhabitants of the 24 municipalities - at all times.
Leveraging the data from these, in combination with InfoNet, the company has developed an investment and renovation plan to determine where new sewers are required, and where existing sewers need to be renovated.
Data inventory
The first step in the process is determining the physical location for new sewers, and the location of new house connections. The sewer database is updated with information from this survey work, and this data will in turn inform forward maintenance plans.
An inventory of a proportion of the pipes and nodes across the 24 municipalities enabled a great deal of information to be input to the GIS database and iSeries. The work began with zoning plans, which show whether houses are connected to the public sewer system (zones depicted in green) and which of them have individual wastewater systems (zones depicted in red).
The company surveyed all pipes and nodes in the green zones with flows greater than 25PE. Where flows were lower than this and the total length of the pipes was over 50m, they surveyed the pipes and nodes. Where the total length of pipe was under 50m but over 10m a simple visualization of the infrastructure was deemed sufficient. Pipes with flows below 25PE and shorter than 10m were not included as they were of minor interest.
In the red zones, the reverse applied: where the total pipe length was greater than 50m the company created a visualization, and where the length was less, the pipes were not registered.
For the inventory, Riobra undertook a GPS survey of the xyz coordinates of around a third of the manholes and associated pipes across its areas, underground surveys of all nodes (equating to around a third of the manholes) and a survey of all the hydraulic structures.
Sewer identification
The company classifies its sewers according to their flows: when the system is not a qualified watercourse, such as a river, but has flows greater than 25PE it is classed as a foul water sewer. Below 25PE, if the flow contains ingress from fields or incoming ditches it is assumed to be a rainwater sewer. If there is no dilution evident, these low-flow pipes are also classified as foul water sewers. If the pipes have not been surveyed, they are classified as rainwater sewers.
The results are displayed in InfoNet for greater clarity. In the Geoplan, themes are used to assign different colors to the different types of sewer: light blue is used for qualified sewers, dark blue for rainwater and brown for foul water. This clear, simple method of identification means it is not necessary to click on a pipe to determine its use.
Information about manholes (such as depth and material) is also collected along with images of the manhole, both of its exterior and surroundings and its interior configuration.
Developing the investment plan
InfoNet is also used to develop the investment and renovation plan, allowing Riobra to indicate project areas so that it can identify investment programs. Again, themes are used to simplify this process - the various project areas are assigned different colors - for instance, projects due to be completed in 2009 are colored red, whereas projects due to be constructed in 2011 are colored brown. It is therefore easy to find the location on a city plan of the various projects and their due build dates.
Implementation and new house connections
For all projects, as-built data and images, critical elements in undertaking new house connection work, are connected to the project areas as a hyperlink. Riobra uses both InfoNet and iSeries for this work, because it needs to collect administrative data and also wants to know the geographical location of the house connection.
Data can be exported from InfoNet to iSeries, and imported from iSeries to InfoNet, so that both databases hold relevant administrative and geographical information. New house connections are created in InfoNet using two connection nodes and a length of sewerage. Some of the data fields draw information from iSeries, and the quality of the data is checked ahead of importing into InfoNet and flagged according to its quality. The new connection request application form that householders must complete is connected as an ancillary hyperlink, as are photographs of the finished work.
Creating a maintenance plan
In InfoNet, maintenance plans are devised by creating thematic maps - for instance, by highlighting pipes where, for example, the sludge depth is greater than 150mm. That way it is possible to plan how often a particular subset of pipes is cleaned. This data is imported from the operational InfoWorks CS model.
Implementation
Riobra undertakes preventative maintenance such as sewer cleaning and surveying as well as reactive maintenance - resolving incidents such as collapses and pipe blockages. Adding data on such incidents to the InfoNet database enables the company to determine if a pattern of collapses is occurring on a particular pipe run, allowing it to consider whether to renovate or replace a failing section.
Using InfoNet
There have been found to be many advantages to using InfoNet, such as the ability to produce clear reports. The solution is also extremely easy to use, and the data flags have proved very useful. It is also possible to export and import data to and from other solutions such as iSeries, ArcView and InfoWorks.
Riobra is considering improvements such as integrating other databases such as iSeries, and exploring the solution’s graphical possibilities.
This article is based on an original presentation by Ilse Arnauts of Riobra to the MWH Soft User Conference in September 2009.