Client:  Municipality of Nea Zichni
Year:    1996

ISSUE
The purpose of the project was the Approval of Environmental Permit for the construction of a Waste Water Treatment Plant in the Municipality of Nea Zichni and the required wastewater transmission pipelines.

SOLUTION
The WWTP was constructed in number 2531 estate, which is located 800m southwest of Nea Zichni and occupies an area of 635m2.
The WWTP was designed to serve a population equivalent up to 4.500 habitats (target year 2050).
The design of pipelines, pumping stations and WWTP was based on a 40-year horizon, while the selection of electrical and mechanical equipment was based on a 20-year horizon. More specifically, the project included:

• external gravity sewer network (with a total length of 580m and pipeline diameters of 200mm) and force main sewer network (with a total length of 600m and pipeline diameters of 90mm); two (2) pumping stations were designed for pumping the wastewater.
• WWTP which treats the incoming wastewater using the treatment process of activated sludge process with extended aeration, nitrification – denitrification and simultaneous stabilization of sludge within the aeration tank. Treated wastewater is discharges via a main force pipeline used for irrigation. In summary the WWTP consists of the following units:
• bar screens
• sand and grit removal
• flow measurement
• denitrification tanks
• aeration tank
• automatic system of measurement – control of dilute air
• secondary sedimentation tank
• pumping station for sedimentation
• pumping station for sludge recirculation
• chlorination tank
• sludge thickener
• mechanical sludge dewatering
• buildings
• instrumentation, mechanical and electrical equipment 
• fencing - landscaping

In the accounted study the exact locations of the construction works were identified while the current situation was analyzed, investigating the state of the natural and human environment. At the same time significant information was offered with respect to the feasibility of the works along with their analytical description.
 
Finally, the extent and size of the caused environmental annoyance from the construction and operation of the works was described, while appropriate methods to treat environmental impacts during construction and operation phase were provided.

BENEFIT
The project was submitted to the public agency responsible for issuing the required Environmental Permit and contributed in the resolution of wastewater management issues in the Municipality of Nea Zichni.