Model Prediksi Kualitas Air Sungai Deli sebagai Air Baku Air Bersih di Kota Medan

Abstract

Deli river flows through the heart of the city of Medan, the length of the river is about 7% km. It belongs to river region group Belawan Belumai-Ular in North Sumatera Province, Indonesia. Local Government water board company called Perusahaan Daerah Air Minum utilizes Deli river as one of drinking water resource for people in Medan.

The prediction of Deli river quality is necessarily important such that to manage the river as a resource for drinking water can be carried out professionally and continuously. Mathematical model can be used to predict changes in ambient water quality due to changes in discharges of wastewater. This dissertation addresses a certain from of water river quality modeling. The main objective is to obtain simple dynamic water river quality which can be implemented in a data limited situation and is compatible with typical complex model, so that the proposed model can be used in integrated modeling of wastewater and river water quality in the future.

A simplified river water quality model was formulated based on a conceptual hydraulic sub-model and simplification of an existing river water quality model. In dynamic modeling, serially connected completely stirred tank reactor (CSTR) are assumed to represent the behavior of a river stream. Each reactor forms a computational element and is connected sequentially to similar element upstream and downstream. The result model was implemented to predict the quality of Deli river. Using sensitivity analysis, the result show that the model is able to be used for predicting the Deli river water quality, particularly related to determining DO concentration.

Linear regression was used to model the drinking water resource planning. The model is utilized for analyzing a relationship between clean water flows with the level consumption of water for the people of Medan, Deli River water flow and the number of people in Medan. Basically the level of water consumption depends on the number of people. Meaning that if the number of people increased, the level of water consumption would increase such that it is necessarily important to plan the drinking water availability.