Researched By: Christina and Khasim


We are testing for alkalinity in our school water because it is important that we understand what is in our school water. Alkalinity is important to have in our school water because if water is alkalinity free it is more likely to be prone to be acidic. Alkalinity helps the water stay stable in pH. It is essential for us drink clean water for health reason, plus us teens need water for our daily diet : ). Read to learn more about alkalinity and if it's found in our school water.

What is Alkalinity?

Alkalinity is a measure of the capacity of water to neutralize acids or hydrogen ions. Alkalinity can sometimes be refereed as "Carbonate hardness". Alkalinity acts as a buffer if any changes are made to the water's pH value. The Alkalinity in the water will help keep the water's pH stabilized. The drinking water and all water should be a pH of 7 meaning that it's neutral.

High alkalinity is good to have in our drinking water because it keeps the water safe for us to drink. The amount of Alkalinity that should be in our water is 20-200 mg/L for typical drinking water. Alkalinity is basically dissolved minerals in the water that help neutralize the water we drink.

Where does it come from?

Most alkalinity in surface water comes from calcium carbonate (CaCO3) that come from rocks and soil. Limestone contains high level of calcium carbonate. The process is enhanced if the rocks and soil have already been broken up before entering the water. The dissolved minerals get into the water through construction and other processes



Leached from rock

 - limestone

·   Leached from minerals

 - dolomite

 - calcite

·   Leached from soil

These are some of the types of minerals and rocks that are sources of alkalinity

Alkalinity also protects our water from acid rain. Below is a picture of how alkalinity protects the waters pH and it's wildlife.


Here is the procedure for testing our school water for alkalinity:

Procedure of Alkalinity Test;

Results :


Amount of Alkalinity found

School of the Future

160 ppm

PS 11

140 ppm

PS 234

100 ppm

PS 42

80 ppm


100 ppm


60.5 ppm

PS 41

120 ppm


100 ppm

PS 116

140 ppm

I.S 131

8O ppm

What do these results mean?

Along with testing our school water we also decided to test the drinking water of the schools' in our area. The test have found that the Alkalinity found in most of Manhattan schools are typical to have in our drinking water. School of the Future's drinking water has the most alkalinity out of all ten schools. This probably explain for our water having a funny taste it cause it's packed with minerals. Beacon has the least alkalinity out of all ten schools tested but this isn't a bad thing. All school water has the right amount of alkalinity.


While doing this test we realized that there was room for error or things that could have made our test not precise. We might have had lost some of the sample water. When adding the Reagent B to the sample, to test how much alkalinity is in the water both of us had a different interpretation of the color pink. This could mean that there's either more or less alkalinity in the water then we actually think

To solve this problem you can make sure that you are careful with the sample water. To solve the problem of testing to see how much alkalinity is in the water and determining if the sample turns the right pink you should have the same person do all the test or the same person determining whether or not the sample turned pink.

The positive part of having alkalinity in your water is that it keeps the water less susceptible to acids. If you have to much of it in your water it means that it is packed with minerals and can cause the water to become fogged. This is called turbidity, which can fog the water and make sunlight very hard to get through. The turbidity causes the plants under the water not to get any sunlight Without sunlight, plants aren't able to give off any oxygen and wildlife suffers. Another thing that can happen if there is to much alkalinity in the water is that the water becomes known as "Hard water". This can have toll on pipes and can cause them give off lead (where apply) which can harm us if we drink it. When the water becomes "hard" it has to many dissolved solids. Dissolved solids are the minerals in the water. Alkalinity is essential for keeping our water protected from acids, like acid rain. It is essential we understand what is in our school water! We hope that this test has helped you understand the conditions of our school water and others around the city.