Project Appreciation and Objectives
The corrosion of concrete used in the construction and lining of sewers and pumping stations leads to the development of holes and potential collapses and represents a significant risk of failure of these critical assets.
Previous research by WRc into predicting septiciity in rising mains and corrosion in grvity sewers, (CP408), identified key factors, indicators and causes corrosion, together with a range of preventive techniques. Key parameters include the alkalinity of the concrete surface, and the dissolved sulphide concentration and pH value of the sewage. However, there are no established methods or procedures available to operators on how best to measure these parameters, to determine current condition or to assess the impact of mitigation measures.
The projects's objectives are:
- To determine which of the available methods are appropriate for measuring the key incidating parameters on different asset types taking into account their effectiveness, costs and limitations.
- Assess the effectiveness of corrosion prevention options using the analytical methods identified on sewers/pumping stations.
Benefits to Clients
- Cost-effective methods for measuring the key parameters and indicators relating to corrosionin sewers/pumping stations.
- Ability to estimate corrosion rates with better confidence and develop cost-effective, proactice mitigating strategies.
- Ability to assess the effectiveness of methods being used to prevent corrosion.
- Identify and assess suitable analytical procedures available for measuring key parameters that contribute to the corrosion of concrete and affect the rate of corrosion.
- Investigate the effectiveness of options for preventing concrete corrosion in sewers ad pumping stations. The identified analytical procedures for measuring key parameters will be used before and after corrosion prevention measures have been applied at a number of sewers and/or pumping stations to determine the effectiveness of the measures.
- Develop asset/method specific guidance to facilitate easy implementation by operators.
A set of practical briefing notes for each of the preventative measures investigated, identifying techniques to measure their effectiveness on-site.
- Septicity in Rising Mains and H2S Corrosion i Sewers
- Surveys of sewers for septicity. Consultancy projects for water utilities.