Sewerage and Stormwater Network Design Works
DESCRIPTION OF WORKS:
Design services carried out by ER-GE consist of two parts: Application design of the sewerage system and the wastewater biological treatment plant.
a) Sewerage System Application Designs:
Initially, a preliminary design report was prepared, in which an overall assessment of the preliminary design prepared by Iller Bank previously was made. Factors such as the existing sewerage system, road condition, basement depths, underground facilities, water supply system and the stormwater system were
assessed in this report. In addition, population projections and wastewater quantities (domestic wastewater flow and projection rate, peak factor, design horizon, pollution loads) were calculated and the base design data and criteria were determined.
The sewerage application design was prepared according to the criteria defined in the preliminary design report and the topographical surveys. Design horizon was selected as 2027 and population was calculated to be 135,000. Concrete and reinforced concrete pipes were used in the sewerage system with 172 km network and interceptor length in total.
b) Wastewater Treatment Works:
Treatment method options likely to be applied for the treatment plants were examined in the preliminary design report, and the facultative stabilization pond system, which was the most economical and most simple in operation among the options examined, was selected. It was planned to construct stabilization ponds in the first step; and later, when the town population and wastewater flow and pollution loads exceed the pond capacity, to add aerated facultative ponds to the system.
The most significant criterion for selecting this system is that no aeration equipment is needed for 15 years until 2005. Aerated ponds will be constructed after 2005, and there will be no power cost until 2005. Also until 2027, power costs will rise only in winter.
Because of the topographical condition of the town, construction of one treatment plant is planned on a 25 ha land near the Habur river where wastewater can be collected and discharged by gravity.
The main collector which transfers wastewater to the locatıon of treatment plant is connected to it at depth of 6.50 m because there is no sufficient slope along the route. Therefore, a lift station is needed. The pre-treatment units comprising of screen and grit removal were designed at the location of the lifting station. Wastewater passes through screen and grit is then lifted to the higher elevations where to be taken into a splitter box, and distributed to the ponds through 0,50 m x 0,50 m box section feeding line. Water transfer between the serial stabilization ponds is provided inside the bank between ponds, through transfer pipes 0.70 m below the water level of the pond.
CONSULTING SERVICES:
Services provided by ER-GE in this project:
- Preparation of the preliminary design report,
- Topographical surveys and measuring,
- Necessary soil investigations,
- Complete implementation design of the plant including all architectural, structural, reinforced concrete, hydraulic, electrical and mechanical calculations,
- Preparation of quantities and cost estimations documents.
CLIENT:
İsmail KOÇ
(The Contractor of Republic of Turkey, Prime Ministry, Southeast Anotolia Project, Head of Regional Development Administration)
DATE: 1992 – 1993
PROJECT COST: 15,000,000 USD
