Emergency Underwater Rehabilitation of the Poti Main Diversion Weir, Georgia

The Dam Safety Project (DSP) in Georgia, which is a part of the Irrigation and Drainage Community Development Project (ICDDP) financed by the World Bank, was implemented by Jacobs during the period August 2003-July 2004. The DSP project included four irrigation dams as well as the main diversion weir on the river Rioni at the town of Poti, the third largest town in Georgia and currently the busiest Georgian port on the Black Sea.

The diversion structure, which discharges flows of 4,000m³/s through 10 identical openings, was constructed in the 1950's to protect the town of Poti from frequent flooding by the river Rioni. Scour problems related to the downstream pool of the diversion structure have been known for almost 50 years. Currently the structure operates at a verge of breakdown endangering the safety of the population in the town of Poti and nearby villages, as well as the important transportation links (Poti port, motorways and railways) and sustainability of the Black Sea coastal zone. Failure of the diversion structure would cause flooding of the Rioni-Khobi Drainage Scheme which has already been rehabilitated under the IDCDP.

As a part of the safety assessment, emergency rehabilitation works have been developed. The implementation of the emergency works by the IDCDP started in October 2004 and were completed in February 2006.

• Introduction

• Inspections and Surveys

• Site Conditions

• Analyses Carried Out

• Recommended emergency Remedial Works

• Conclusion