There are many different natural waterways in Christchurch, eg. rivers, streams, creeks and many more. Some waterways are manmade like water races, stormwater systems and artificial drains. Waterways have many uses like making electricity, recreation and lots more.
If you wash your car on the driveway the chemical infested water will go down the drain and into the rivers. However if you wash your car on the grass, the chemicals in the water will drain down into the aquifers; but while the water is draining down, the dirt acts as a filter and stops the chemicals from draining into the aquifers.
Rainwater starts off in the gutters then goes down a pipe which leads to the stormwater drains. Unfortunately that water goes to the waterways. When waterways get polluted it may have a flow on effect because the polluted one might join onto other waterways and make others polluted.
Many habitats need water so you will usually find habitats around waterways. A habitat is an area where lots of animals live eg. frogs, invertebrates, macroinvertebrates, fish and many more.
Different things can have good effects on a habitat or bad effects on a habitat. An example of this is a river might flood and destroy the animals home which will badly affect the habitat. Maybe a habitat is lacking water and a river created will have a good effect on the habitat. If there is a river flowing through a habitat and humans litter in it, it will become polluted and then this will again badly affect habitat. The quality of the water in a habitat is very important for instance if the water was too hot, no fish, frogs or macroinvertebrates would live or make their habitat there. The animals in the habitat rely on the waterways for food as well. Everything in a waterway is connected where each plant or animal relies on something else to survive.
There are many different ways to see if a waterway is healthy, even animals can even tell you. Here are a list of them:
If the waterway is unhealthy it will have macro invertebrates like snails, slugs and worms this is because these macroinvertebrates can survive in polluted water or fresh water. If the waterway is very healthy it will have macroinvertebrates like stone fly, mayfly and many more.
The algae can tell you if it is an unhealthy waterway because it will have a thick mat of algae or long strands if it is a poor waterway, and it will have a thin mat of algae on the rocks if it is healthy.
If it is a bad waterway it will have lots of loose dirt hanging and falling into the waterway. This makes the water murkier which makes the invertebrates suffocate. If it is a good waterway it will have no dirt with access to the waterway.
If the waterway is bad it will be very murky and you cannot see for more than 5 centimeters. If it is a good waterway you will be able to see up to 95 centimetres.
If it is a bad waterway it will be warm or warmer than 20 degrees. If it is good it will be colder than 15 degrees. The colder the water the more the macroinvertebrates will like it.
Method - Testing our Waterways
We have visited many waterways to assess them. Here is how we assessed them: We used the In-Stream And Riparian Habitat Survey. We also fished out invertebrates and macroinvertebrates and we put the different species in different compartments. Inside the In-Stream And Riparian Habitat Survey there was a chart that had different scores for different visual signs of river health. We also used a turbidity tubes to check the turbidity.
Waimairi schools Stormwater Drain
Waimairi schools stormwater drain could be improved lots because it has no trees also lots of erosion. There is a graph above telling you the scores out of 8. We have a list of things we could improve on.
There are not very many stones on the river bed, in fact about one quarter of the base is dirt. Stones are way better than dirt because stones provide hiding places for invertebrates and invertebrates don't like dirt because it has no oxygen in it .
There was no algae in the waterway. Algae is good because it provides a home for the invertebrates and also a food source .
There is lots of erosion. The dirt is piling up and eroding into the waterway which would be suffocating any microinvertebrates.
There was no shade on the waterway there was only grass on the water's edge which is bad because invertebrates and fish can't survive in warm water.
We need to respect the land and waterways. Here is a list of changes we could make :
- We could plant lots of native trees and bushes to attract native birds and native fish. It would also hold the bank together and provide shade for the macroinvertebrates and fish.
- We could dig out silt on the waterways bed and place stones on the waterways bed instead. This would help the invertebrates hide from predators because they can hide behind stones but not in dirt because they can't breathe.
- We could remove all the junk from the waterway.
Why we should make these changes
We should start helping to clean the waterways because ...
1. If we pollute the waterways when we are doing recreation we will be swimming in polluted water which could make us sick .
2. There is a maori word called Kaitiakitanga, and it means respect the land and water. Maori want to be able to use the land and waterways forever. Traditionally, when they died, fellow people would take him/her to the river and let the fish eat the skin so that he is part of the land forever.3. If we pollute the waterways the pollution will affect the fish, which if we eat they will affect us. So that is why we should make these changes.