Presentation from Algeria - Mr CHARIKHI

General presentation


The ANRH is made of a Head department and 4 regional headquarters (East, Center, West and South).
It depends on the Ministry of equipment and territory management. It is divided into 6 departments :

Introduction

The runoff in Algeria mainly concerns the northern part of the country. In the north of the line Bechar-Laghouat, it is spread over a surface area of about 330,000 km²
The time distribution of the rainfall as well as the lithologic and morphologic nature of the catchments give :

Hydrographic network

In the framework of the Med-Hycos programme, Algeria is divided in 17 large hydrographic basins, divided into 3 groups : In our case, we will only focus on the basins going to the Mediterranean sea.
These basins drain the Tellien Atlas and the Saharan mountains. They are spread over a surface area of 130,000 km² and receive an average rainfall varying from 400 mm to 1,500 mm. The mean annual supply is estimated to 11 billion (milliard) m³.

The first selected station for the Med-Hycos Programme is :

Basins taken into account for this programme

Within the framework of the Med-Hycos programme, only the important basins have been taken into account : This choice was made according to the two following criteria : These basins represent by themselves, a surface area of about 79,650 km², that is 26 % of the total surface area of northern Algeria, and totalise a supply of nearly 3 billion m³ (supply at the outlet of these basins).

Perspectives of development of the national hydroclimatological network

A monthly discharge of a given month cannot be known sooner than several months later, in the present conditions of equipment and management of the network. This delay can be reduced significantly using automatic devices.

With this in mind, ANRH inscribed in its programme a general study of modernisation of the network.

This modernisation will allow :

The desired objective is to obtain a totally monitored network and a network of remote monitoring via satellite.

This will permit the programmers to obtain sufficient information (in quantity and in quality) to provide the water demand while respecting environment protection.

Proposition

In order to improve the cooperation between the international hydrological services and resources management, ANRH proposes 8 hydrometrical stations (in the 7 basins) and whishes this set of stations to be part of the world network of reference stations.

Object of the study

The bulk of the national hydroclimatological network was set up during the 70's and equipped with classical measurement devices. It is now a little obsolete, not of high performance and inadapted to a real time monitoring system and a dynamic resource management.

The nature of the sensors and the recording systems on this network, the pneumatic power and energetic systems of the devices, the methods for taking samples and measuring, the calculation methods and the data transmission multiply the sources of errors and are at the origin of long delays between the acquisition of the data and its process.

The successive periods of drought observed in Algeria during the last two decades, and their impact on the water resources and the environment pointed out the inadequacy of this network and the need to possess tools and dynamic management systems in matter of water resources.

Today, taking into account the improvement of technologies in matters of acquisition, storage and transmission of data via satellites, and the improvement in matter of mathematical modelling, the forecasting and simulation of hydroclimatological phenomena, we could consider real time monitoring and dynamic and large basin scale management.

The Algerian ministry of Equipment and Management of the Territory plans, via ANRH, to get, master and start up such tools, firstly in the larger regions of hydraulic planification of Oran, Algiers and Constantine where important hydraulic works have been carried out, and where the water demand grew in an important manner.

Description of the present network

The network presently managed by ANRH is made of : The hydrometrical stations are equipped with staff gauges and pneumatic limnographs with air alimentation through compressed air bottles and powered with cells. The discharge measurements are made while taking gaugings with current meters on a perch or on winch.

The monitoring of the quality of water was operated for about ten years via a network of 120 observation points, mainly using large reservoirs dedicated to the supply of drinking water and the main wadis. The analysis made from manually taken samples, using about thirty physico-chemical and bacteriological parameters.

Present organisation of the path of the information and the process of the data

The chain of data processing presently used, relatively manual, is mainly done depending on the equipments installed and the observation techniques, and the used measurements.

After the collection of data at the stations, the measurements and records are processed at three different levels, corresponding to the regional organisation at ANRH.

At the level of the hydrological sector

The sector is the basic cell of ANRH and its main aims are :

At the level of the Regional Antenna

The data coming from the sectors are controlled and key entered in computers (the Regional Antennas are now equipped with micro-computers).

For the last years, the drawing of rating curves of the stations are done at the level of the Regional Antennas.

On the other hand the Regional Antenna proceeds to the fundamental physico-chemical and biological analysis and processes the data dealing with the quality of water.

A mini data bank is built at the level of the Antenna.

The processed data, as well as the original recordings are then transmitted to the Central Direction.

At the level of the Central Direction

The data coming from the Regional Antennas are, at the level of the Central Direction of ANRH, tested and complementarily processed, validated and feed in the end the National data bank of water resources.

These data are then processed for :

Carte de situation des stations hydrométriques


 
 
 

Carte de la qualité des eaux superficielles

 
 

Liste des stations proposées