The aim of this study was to measure the water quality of the Sulby River in the north of the Isle of Man at 4 different locations. The water quality features.

The aim of this study was to measure the water quality of the Sulby River in the north of the Isle of Man at 4 different locations. The water quality features measured were dissolved oxygen, turbidity, pH and water temperature.

The river is begins in the hills above the Sulby reservoir, feeds the reservoir then continues down the valley and through Sulby village then Ramsey town until it reaches the harbour at Ramsey and enters the sea. It is the longest river in the Isle of Man and supplies the largest amount of fresh drinking water to the Manx population.

Test site 1Brandywell, river source

Test site 2Druidale, tributries meet

These next three slides are the course of the river.

Test site 3Tholt-y-will

Test site 4Garey ford

Turbidity:Turbidity is the measure of the relative clarity of water. Turbid water is caused by suspended and colloidal matter such as clay, silt, organic and inorganic matter, and microscopic organisms. Turbidwater may be the result of soil erosion, urban runoff, algae blooms, and bottom sediment disturbances which can be caused by boat traffic and abundant bottom feeding fish. Turbidity should not be confused with colour, because darkly coloured water can still be clear but not turbid.

Water temperature:The air temperature is directly affected by the land temperature. Water temperature is slower to react to changes than land temperature.Aquatic animals are sensitive to changes in water temperature and require a certain temperature range to survive and thrive. If the water temperature is outside that range for along time, organisms can be stressed and die. However, Most aquatic organisms are cold-blooded. This means that the temperature of their bodies match the temperature of their surroundings. Temperature also affects the amount of oxygen water can hold. Cold water holds more oxygen than warm water, and all aquatic animals need oxygen to survive. Temperature also affects the rate of photosynthesis by aquatic plants, and the sensitivity of organisms to toxic waste, parasites and disease. Warm water discharged from factories, the removal of trees and vegetation that shade streams and urban runoff can cause temperature changes that threaten the balance of aquatic systems .

Dissolved Oxygen: Dissolved Oxygen is important to the health of aquatic ecosystems. All aquatic animals need oxygen to survive. Natural waters with consistently high dissolved oxygen levels are most likely healthy and stable environments, and are capable of supporting a diversity of aquatic organisms. Natural and human-induce changes to the aquatic environment can affect the availability of dissolved oxygen. Dissolved Oxygen % Saturation is an important measurement of water quality. Cold water can hold more dissolved oxygen than warm water. High levels of bacteria or large amounts of rotten plants can cause the % saturation to decrease. This can cause large fluctuations in dissolved oxygen levels throughout the day, which can affect the ability of plant and animals to thrive. Certain water bodies, like swamps, naturally have low levels of DO in the water. This is because decaying matter uses a lot of oxygen during decomposition – or more accurately the micro-organisms that break down the decaying matter use up much of the oxygen in the process. Much of the oxygen in water comes from plants during photosynthesis and also from air as wind blows across the water’s surface. Where the river has a lot of ‘white water’ also has higher oxygen content as the air bubbles mix with water as it tumbles over the rapids and waterfalls

pH:pH is a measurement of the acidic or basic quality of water. Most aquatic animals prefer a range of 6.5 to 8.0 they are adapted to a specific pH level and may die, stop reproducing, or move away if the pH of the water varies beyond this range. Low pH can also allow toxic compounds to become more available to aquatic plants and animals. This can produce conditions that hurt aquatic life. pH can be affected by wastewater discharges, drainage from mines, and the type of rock naturally found in the area.

Turbidity: I would expect the turbidity to be high at site 1 because it is more of a swamp than a river with a lot of suspended matter such as peat. There was a lot of plant life which would add to the amount of organic matter clouding the water.

Further down the river at site 2 I would expect the turbidity to be low because the bottom of the river is stony and can be clearly seen. Also, there is little disturbance in the way of traffic or animals.

At site 3 the water current is strong but very clear so I predict that this site will also have low turbidity.

I expect that the turbidity will also be low at site 4 because the rocks and stones can be clearly seen on the river bed.

The Water Temperature:

I predict that the water temperature will be lower than the air temperature which is 12/14°C at all the sites because it is a cold, autumnal and wet day. However, I think that the water temperature will be even colder on higher ground at sites 1 and 2 and slightly warmer closer to sea level where the river is more sheltered and the air temperature is warmer.

The acidity:

I predict that the water acidity in general will be low because there are hardly any factories or industry along the river banks. At the source of the river the acidity level will be very close to the pH of natural rain which is between 5 and 6, but at the second site I expect the water will be very acidic because the river passes over peat which has a high pH level. As the river leaves the peat area I predict that the pH levels will fall to the healthy level of 7, which is a level at which most plants and animals thrive.

Dissolved oxygen content :

I predict that in general there will be a lot of dissolved oxygen in the river because the water is very cold and there is no pollution because there is no industry along the river banks. Also, although I saw very little animal life present during the exercise from past experience I know the river has lots of fish living there.

At the source, site 1, I predict that there will be less dissolved oxygen because there are a lot of rotting plants and the river bed is peaty. Site 2 is where two tributaries meet and there is a lot of white water as it flows with a lot of energy so I expect there to be a high percentage of oxygen saturation. Site 3 also has a lot of white water as the river falls over waterfalls and rocky areas and site 4 is clear and cold so I predict they will both have a lot of dissolved oxygen.

Water collection procedure:

Equipment:sampling jarlidtimergloves

Method:

1. Remove lid from sampling jar. 2. Wear protective gloves. 3. Rinse the jar 2-3 times with the stream water. 4. Hold the jar near the bottom and plunge it below the water surface. 5. Turn the submerged jar into the current and away from you. 6. Allow the water to flow into the jar for 30 seconds. 7. Cap the full jar while it is submerged. Remove it from the river immediately.

To measure turbidity:

Equipment:Sampling jarSecchi disk iconTurbidity chart

Method:

1.Adhere sticker on the inside bottom of the sampling jar, slightly of centre. 2.Fill the jar to the turbidity line located on the outside label. 3.Hold the Turbidity Chart on the top edge of the jar. 4.Looking down into the jar, compare the appearance of the secchi disk icon in the jar to the chart.5.Record results.

To measure water temperature:

EquipmentGloves ThermometerSampling jar

Method:1.Wear Protective gloves. 2.Put the water thermometer under the water for 1 minute. 3.Remove the thermometer from the water, record the temperature as degrees Celsius.

To measure dissolved oxygen:

Equipment :Sampling jarThermometerSmall test tubeDissolved Oxygen ChartTimer

Method: 1. Record the temperature of the water sample. 2.Put a small test tube into the sampling jar, remove it making sure no air gets in. 3.Put the Dissolved Oxygen tablets in to the test tube. 4.Screw the cap on. 5.Mix the Dissolved Oxygen tablets for 4 minutes. 6.Wait 5 minutes for the colour to develop. 7.Compare the colour of the sample to the Dissolved Oxygen colour chart . 8.Record results.

To measure pH:

Equipment Large test tubepH tabletspH colour test tube

Method:

1.Fill large test tube to the 10ml mark. 2.Add one pH tablet. 3.Mix until tablet has dissolved. 4.Compare the colour of the sample to the pH colour chart.5.Record results

Date: 26/10/09Time of year: autumn Current weather conditions: windy with light rainCloud cover: overcast Air temperature: 12/14°C

Parameter Site 1 Site 2 Site 3 Site 4

Date 26/10 26/10 26/10 26/10

Location Brandywell Druidale Tholt-y-will Garey Ford

Air Temp 12°C 14°C 12°C 14°C

Turbidity 0JTU 0JTU 0JTU 0JTU

Water Temp 10°c 10°c 12°c 12°c

Dissolved Oxygen - %age saturation

71% 71% 74% 74%

pH 6 9 8 7

This is site 1, the source of the river and as we can see on this photo the river is swampy with a peat bed, a slow water flow and thick vegetation with little sunlight getting to water. The weather was overcast, and raining and this point is high above see level.

This is site 2 and as we can see it is the point at which two tributaries converge. The river is very narrow and there is some white water. The water is very clear with lots of stones and vegetation around the river. The weather is still very cold.

Two tributaries meet

This is site 3 where the river has widened with some white water and the still water is very clear. There are a lot of leaves around about the river so there is lots of shelter from trees. The water temperature has warmed slightly.

This is site 4 the river is very wide, shallow and slow moving, the river is quite sheltered. Even though there is tree cover there are no leaves on the trees and there is plenty of light getting through.There are ducks in the water. The water temperature is the same as site 3.

Turbidity: Site 1 the data shows that the test disagrees with my hypotheses maybe because the rain water had only recently landed and didn’t have time to mix with the soil ground. Site 2 data agrees with my hypotheses, showing that the water was clear because there was no disturbance by animals or factories. Site 3 data agrees with my hypotheses because the strong current and the stony bottom stopped any disturbances in the river bottom. Site 4 data agrees with my hypotheses because again there is a stony bottom stopping disturbances.

Water Temperature:The water temperature at the first two sites agrees with my hypotheses because it was a cold wet day and the first two sites were up on a bleak hill top. Further down at the last two sites the data agrees with my hypotheses because the sites were much more sheltered.

The Acidity: At the source the data agrees with my hypotheses because the rain water has had little time to mix with the peat so the water still had the same acidity levels as rain. The second site agrees with my data collected because the river passes over peat which has a high acidity level. The lower course sites, from the data I collected agrees with my hypotheses because there is no more peat land and no factories so the acidity level drops along the lower course of the river.

Dissolved Oxygen:At site 1 the data I collected disagrees with my hypotheses probably because the water was very cold. Site 2 data agrees with my hypotheses because the weather was cold and there was some white water. Site 3 also agrees with my hypotheses because there were waterfalls mixing oxygen into the water. Site 4 hypotheses agrees with the data I collected because it was very similar to site 3 with cold weather

This data collection exercise was very limited. Results only show the quality of the river water at one fixed point in time. If I was to do this experiment again with unlimited time and resources I would test even more sites along the river at different times of day; during different seasons and weather conditions; and I would do it when the reservoir was discharging because I believe this would make a big difference to the results. I would use more specialised equipment for example a Winkler Titration Kit would have given me a more specific result for the levels of dissolved oxygen and a secchi disk to improve the turbidity measurements.On the whole the exercise was informative and produced some interesting results. It gave an overall picture of the Sulby River showing it to be in a very healthy condition and capable of supporting a good community of plant life and animals.