Submarine Outfall Design Works
The project covers production of the network, intercepting collector and treatment and sea outfall designs of main plan and applicability reports, geotechnical and sea investigations of a whole sewerage system requiring connection of Marmara Ereğlisi - Yeniçiftlik – Tekirdağ shoreline residential and the surrounding societies and all establishment. The project area covers a shoreline of approximately 40 km.
a) Sewerage Main Plan and Applicability Design,
3 reports were prepared about the subject. Studies about the development plan, population projections and distributions were made in the first report. More detailed and advanced sewerage systems were created in the second report, the drainage area was specified and the design criteria for the treatment plants were determined. Treatment method options were examined, utilization possibilities of the treated water were assessed and recommendations for final discharge were developed. Short, medium and long term basic project data were specified and evaluated for each stage, and the preliminary dimensioning calculations needed particularly for phasing the treatment plants were carried out. In the third report, treatment plant dimensioning calculations according to preferences of the Employer and the sea floor mapping results were evaluated, and the calculations needed to determine lengths of sea outfalls were made.
There are 3 main drainage catchment areas in the project area showing apparent topographical differences. Implementation designs of the sewerage network including 1,000 km network, interceptor and collector were prepared to serve a population of approximately 650,000 according to the population projection for year 2030.
14 pumping stations were planned in the catchment area, one of which will transmit wastewater to the treatment plants. 10 Highway lateral crossings (9 in 1st stage, 1 in 2nd stage) and 4 river crossings (2 flush and 2 with bridge) were planned.
ACP pipes were used in forcemains and concrete pipes were used for gravity pipes
b) Wastewater Treatment Plants,
Alternatives for 3 different treatment processes to be arranged in the project area were examined and the best treatment system was selected. As the biological treatment options, active sludge systems and fixed film systems were evaluated and compared in functional and economical aspects.
For the demand of year 2005 the most economical treatment method for all three treatment plants was specified as stabilization ponds. In addition to the ponds planned for 2005, facultative aeration ponds or adding aerators to the stabilization ponds were foreseen to meet the medium term (2015) and long term (2030) demands.
Sea outfall is assumed for wastewater discharged from 3 individual treatment plants proposed for the project area. Locations and lengths of the outfall lines were specified based on the design criteria and by utilizing the existing oceanographic data. Sea floor surveys and preliminary evaluation and dilution calculations were carried out to provide batimetric maps required for the final design. According to these calculations; it was found out that it was possible to ensure the desired sea outfall criteria if the lengths of outfall lines 1 and 2 would be 1,000 meters, and the outfall line 3 would be 1,200 meters, respectively.
CONSULTING SERVICES:
ER-GE carried out the following services under the scope of this project:
- Master plan and feasibility study,
- Geotechnical and sea floor surveys,
- Preliminary designs of the sewerage network and the interceptor systems,
- Implementation designs of wastewater treatment plants,
- Preliminary designs of the sea outfall facilities.
CLIENT: Provincial Bank General Directorate
DATE: 1992 – 1994
PROJECT COST: USD 60,000,000