Water treatment

1 ESO - 2012/2013

Introduction

This activity, called La Ruta del Agua (The Route of the Water) was very interesting to understand the importance and meaning of water as the main source of nourishment. Its value cannot be overestimated, it's essential for all life on this planet.

For thousands of years, humanity has been aware of the importance of water. In Rome, a couple of thousand years ago, it was considered to be one of the biggest crimes to pollute the water.

Today, in our advanced and modern society, we are rapidly destroying water's life-giving capacities. Increased population, industrial wastes and agricultural chemicals are contaminating our water sources.

The next slides explain the activities in the project.

Introduction

This activity has four different parts:Audiovisual

Workshop

Visit to the water treatment plant (A Telva) in Cambre (A Corua) and the reservoir of Cecebre.

Final project and presentations.

Introduction

During this activity, you watched a video about the properties of the water.

Then, the monitor explained to you the importance of the reasonable use of water, and you shared each other you point of view about it.

Everybody became aware of how important is to save water and to keep it clean.

Audiovisual

Workshop

Water quality is a term used to describe the chemical, physical and biological characteristics of water, generally in terms of suitability for a particular or designated use.

Water-quality monitoring is the process of sampling and analyzing water conditions and characteristics.

In this workshop you monitored the water quality of different samples.

Workshop

You studied some parameters such as temperature, pH, suspended solids...

Parameters can be:Physical: temperature, dissolved oxygen, suspended solids.

Chemical: nutrients, heavy metals, pesticides.

Biological: aspects of the living environment (from microscopic algae and invertebrates to macrophytes and fish).

Workshop

You analyzed the turbidity of the water.

You filtered the samples and you could see that the water was really clean.

You also analyzed the presence of suspended solids, the foam on the water, the temperature and the PH.

Water treatment plant

After the workshop, you visited a water treatment plant, called A Telva, in Cambre (A Corua).

Water treatment plant

You visited the control room, where the monitor explained to you the processes used in water purification.

Water treatment plant

The water to be treated in this plant comes from the River Mero, and the stages are:Pre-treatment.Pumping and containment: the water is pumped from its source.

Screening: The first step in purifying surface water is to remove large debris.

Oxidation, coagulation and flocculation: Addition of chemicals to assist in the removal of particles suspended in water.

Water treatment plant

Sedimentation: water exiting the flocculation basin may enter the sedimentation basin. It is a large tank with low water velocities, allowing floc to settle to the bottom.

Filtration: After separating most floc, the water is filtered as the final step to remove remaining suspended particles and unsettled floc.

Chlorination: process of adding the element chlorine to water to make it fit for human consumption.

Final process: pumping of treated water from the water treatment plant to a service reservoir from where water is delivered.

Water treatment plant

Then, you went to the lab and you took part in a small-scale demonstration of the process explained before.

Cecebre Reservoir

Finally, you visited the Cecebre Reservoir, located on the Mero River.

Next to the reservoir, there is a bird observatory and you studied the flora and fauna of the area.

Final Project

To finish this experience, you will have to create comics, ppt presentations, cards, etc. explaining the different stages that a drop of water reaches since it comes out of the river until it arrives at our home.

The last day, you will present your projects to the rest of the classmates.