The Czech Republic’s first-ever submerged aerated filter (SAF) wastewater treatment system has been installed in the village of Drínov, 30km north of Prague. The plant is part of a £1.5m municipal sewerage scheme to help clean up the local environment by centralising wastewater collection and reducing the impact of poorly maintained septic tanks on surrounding surface waters.
The high-performance aerated filter – HiPAF – designed and manufactured by UK package treatment specialist WPL, was specified by the municipality’s engineering consultant prior to tender. The plant is designed for 620 population equivalent and comprises four units.
The primary settlement tank, a SAF for biological treatment and a final settlement module are connected in series. In addition, effluent passes in a circular stream from the primary settlement tank to a robust aerobic digestion system – RADS – and back, which significantly reduces sludge output and extends desludging intervals without use of chemicals.
Discharge is to a local stream, which meant high environmental standards of 22mg/l biological oxygen demand (BOD), 25mg/l suspended solids and 12mg/l ammonia were required. Phosphate removal was also specified by the environmental regulator.
Groundwater challenge
The high level of the groundwater in the region posed a challenge to the installation, which had to be installed above ground. To mitigate the visual impact of the treatment plant on the rural landscape, soil from nearby sewerage excavation works was used to cover the installation.
The earthworks will be seeded with grass in the spring to further improve the aspect. In addition, the walk-in kiosk housing the control panel and washroom facilities was clad with stone, also for aesthetic reasons.
Frantisek Mikulinec, WPL’s sales manager for central Europe said, “I am very pleased that WPL is the company to introduce SAF technology to the Czech market.”
EU finance
Finance for the project comes largely from EU cohesion policy funds, which provided 15% of the finance and will provide support to help countries comply with the Urban Waste Water Directive. The project also had the full backing of the municipality, which will be responsible for operation and maintenance of the plant
The Mayor of Drínov, Jitka Bockova said, “Improving the quality of the environment and surface waters for the Drínov community was a priority for me when I took office and better management of wastewater plays a major role.
“EU regulations like the Water Framework Directive are an important driver for raising environmental standards and can help smaller villages access funding. Municipalities need technologies that provide robust treatment and are simple to install and operate, which is why I was impressed with WPL’s HiPAF.”
