Effects of Industrial and Domestic waste materials on Water Alkalinity
in Msimbazi Stream.

**Country:** Tanzania

## City: Dar es salaam

**Name of School:** Tambaza Secondary School

**School Location:** Latitude 06.80157, Longitude 039.27723 and Altitude
14m**.**

**Student:** James Bwimbo, Diana Godon , Tambaza High School

**Advisor:** Fredson Fredrick, Tambaza High School

# Abstract

This project investigated the effects of industrial and domestic wastes
on water alkalinity level in Msimbazi stream in Dar es Salaam City,
Tanzania. GLOBE students from Tambaza High School obtained information
from direct field observation and laboratory experimentation. The GLOBE
students' alkalinity and pH data used in this study were collected once
per week in each selected study site from March to April 2005. They
checked water pH and alkalinity on three selected locations. One of
which was near the stream mouth, others were at Matumbi and Vingunguti
areas. Average values were obtained for each study area and compared
with standard alkalinity and pH. From comparison it was concluded that
waste materials were not seen to lower water alkalinity. Waste disposal
and horticultural practices were not in conformity with agreeable
standards.

# Introduction

![](media/image1.jpeg){width="2.209722222222222in" height="3.875in"}One
of the greatest challenges currently facing the environmental sector
worldwide is the rising of environmental pollution. Pollution is the
principal threat to the environmental sustainability. Pollution implies
the physical additional of materials to the place where it is not
required. This challenge made Tambaza High School GLOBE students to
investigate water pollution in Msimbazi stream so as to alert Dar es
Salaam city council to conserve the stream.

For several years, wastes from industries, domestic and other human
activities were polluting the stream. Disposal of domestic and sewage
was the main problem of the pollution in the stream. People living along
the stream were being disposing domestic waste materials directly to the
stream.

An area famous known as Kaoshe near Vingunguti ward is highly polluted
by oil from car washing, soap and detergents.

Most of Industries in Kipawa Industrial area, and Buguruni disposes
sewage and other industrial wastes at an area known as SPENKO. At this
place, some of wastes are draining into the stream. People living around
this area have been affected by this system of disposing wastes.
Currently, they are bitterly complaining about this kind of pollution
since they are no longer growing vegetables at the area. This situation
has lowered their incomes.

Also at this particular place the water of Msimbazi stream changes its
colour and odour due to the presence of waste materials.

.

Study Area Description

The study was carried out along Msimbazi stream, which is approximately
60km long. The stream is situated almost at the center of the Dar es
Salaam City. It lies approximately between the boundary of Ilala and
Kinondoni municipals. The river pours its water in the Indian Ocean
through Salander Bridge. The area is characterized by high day
temperature above 30^0^C.

Reasons for selecting this Area

The area was selected because; it is among the areas that are highly
affected by major causes of water pollution and inadequate facilities
and skills to solve water pollution.

The state of Msimbazi stream

![](media/image2.jpeg){width="3.375in" height="4.5256944444444445in"}

Observations made by study team showed that polythene bags and bottles
floating on top and the sides of the stream pollute the stream, water
change its colour, odour smell around the stream and decrease in depth
of the stream due to accumulation of mud resulted from inappropriate
horticultural practices in some areas.

## Classification of pollutants

## Biological pollutants

![](media/image3.jpeg){width="2.6041666666666665in"
height="2.8097222222222222in"}

Biological pollutant indicators observed in the area were horticultural
activities along the stream that loosen the soil, making it easily
eroded by erosion agents such as wind and water.

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# Physical pollutants

![](media/image2.jpeg){width="1.96875in" height="2.640277777777778in"}

![](media/image4.jpeg){width="2.5in" height="1.91875in"}Physical
pollutants observed in the areas of study were disposing of the wastes
from Vingunguti main abattoir channeled to the main stream, washing of
cars along the streams, disposing of sewage, dumping of domestic and
industrial wastes, and throwing of polythene bottles, bags and papers in
the stream.

# Chemical pollutants

Some oil drops and coloured materials were seen floating on the stream
nearby industries. Moreover, agro-chemical fertilizers applied by local
horticulturists along the stream, soaps and detergents from car washing
sites were also seen as part of materials, which polluted the stream.

# Research Hypothesis

Industrial and domestic wastes lower water alkalinity because of high
level acidic created by waste materials.

# Research Methods

![](media/image5.jpeg){width="4.25in" height="1.7347222222222223in"}
Alkalinity and pH data were collected using GLOBE protocols. We
collected water samples from three sites and we tested them in the
laboratory. We titrated water samples against strong mineral acid using
phenolphalein as an indicator. pH of the water sample was tested by
using universal pH indicator. The main information that we were looking
for was the alkalinity level in order to test our hypothesis.

![](media/image6.jpeg){width="5.8125in" height="3.2916666666666665in"}

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# Measurement results from February, to April 2005

+------------------------------+-----------+---------------------------+
| Day of test                  | PH        | Alkalinity (mg/1)         |
+------------------------------+-----------+---------------------------+
| February                     | 8.0       | 153                       |
|                              |           |                           |
| 1^st^ week                   | 7.5       | 144                       |
|                              |           |                           |
| 2^nd^ week                   | 9.0       | 148                       |
|                              |           |                           |
| 3^rd^ week                   |           |                           |
+------------------------------+-----------+---------------------------+
| March                        | 9.0       | 150                       |
|                              |           |                           |
| 1^st^ week                   | 8.0       | 146                       |
|                              |           |                           |
| 2^nd^ week                   | 8.5       | 143                       |
|                              |           |                           |
| 3^rd^ week                   |           |                           |
+------------------------------+-----------+---------------------------+
| April                        | 7.5       | 151                       |
|                              |           |                           |
| 1^st^ week                   | 8.0       | 155                       |
|                              |           |                           |
| 2^nd^ week                   | 8.5       | 160                       |
|                              |           |                           |
| 3^rd^ week                   |           |                           |
+------------------------------+-----------+---------------------------+
| **AVERAGE RESULT**           | **8.2**   | **150**                   |
+------------------------------+-----------+---------------------------+

# Analysis

**Alkalinity**

Alkalinity is the amount of buffering material in the water. If a body
of water has an abundance of buffering materials (high alkalinity), it
is more stable and resistant to changes in pH. If a body of water has
very little buffering material (low alkalinity), it is very susceptible
to changes in pH. As increasing amounts of acid are added to the stream
and lakes, their buffering capacity is lowed. If the surrounding soils
and rocks supply additional buffering materials, the alkalinity may
eventually be restored. Even a temporary loss buffering capacity can
permit pH levels to drop to the level harmful to aquatic life. When a
lake or stream has too little alkalinity typically below 100mg/1, a
large influx of acid could consume all the alkalinity and thus drop the
pH of the water to the level harmful for fish, amphibians and
zooplankton.

**pH**

A pH of 6.5 to 8.2 is optimal for most of organisms. Rapidly growing
algae or submerged aquatic vegetation remove carbondioxide from water
during photosynthesis, significantly increasing pH level. pH level
greater than 9.0 begin to be harmful to salmons (trout). Rainwater
naturally has a pH of 5.5. pH level less than 5.5 is harmful to
freshwater shrimps, snails and clams.

Acidic \< 6.5 pH and Basic \> 7.5 pH.

Our measurements in pH ranged from7.5 to 9.0

# Misleading factors

-   Some points were difficult to reach which could be useful in this
    study

-   Absence of alkalinity test kit as recommended by GLOBE program

-   Time limit for both students and teacher

# Conclusion

From analysis of our different forms of data, the study discovered that
the hypothesis was not wholly correct. The industrial and domestic
wastes disposed in the stream were not lowering water alkalinity.

**Discussion**

The research we have carried out can be of use to the city council, so
that they can understand the water conditions of the stream. This can
help them to make decisions on how to protect and conserve the stream.

## Way forward

The study team should consult the Dar es salaam City Council Authourity
to explain what they had investigated and see to it that all parties
involved in the pollution of Msimbazi stream are advised to minimize
activities of degrading the stream.

The study team needs to lengthen time for studying the stream so as to
get more stable results, which could be used for generalization of
outcomes.

# Bibliography

1\. [www.globe.gov](http://www.globe.gov/)

2\. The GLOBE teachers'book

3\. Www. gogle.com

4\. Western U.P. (2004), Water Chemistry. Center for Science, Math, and
Environmental

Education, Michigan Technological University.

5\. Sibenik (2003), Local discoveries, global understanding. GLOBE
Learning Expedition.

6\. K. K. Shauna (1978) Chemistry practical, New Delhi India.