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TUTORIALS, GUIDES & INFORMATION

Participants in the Essex RiverWatch complete observations of rivers and may optionally complete water quality surveying. Please carefully read through all of the information below before registering your interest in taking part. 

HEALTH & SAFETY AND PRACTICAL ADVICE

After sending an email to the Essex RiverWatch, you will work with the Essex and Suffolk Rivers Trust to select an appropriate river site to survey regularly. You then need to attend training, either online or in person.

 

On your first site survey we recommend that you only make visual observations and only perform water quality monitoring from the second survey onwards. 

 

You never have to complete any water quality monitoring if you choose not to, as surveys can be completed with just visual observations.

The below are some things to consider about health and safety. You will also need to attend mandatory training in either in in person or online session, to read and understand the risk assessment and to have signed to confirm this.

Your survey site must:

  • Be legally accessible to you. You must own the land, have permission from the land owner, or be on public land.

  • Be safe to access year round. There must be a point where you can access the river where you are in little danger of slips, trips, falls or other injuries. It should be away from public highways to avoid any issues regarding vehicles, but close enough to allow access to an ambulance should you or someone you are with require one. You must also be able to get to your site, be that on foot or by car/public transport. If going by car, consider if you have a safe parking location. Solid structures such as bridges can make for a good sample location.

  • Be somewhere you are willing to go. The preference is for this to be a place close to your home, work, or other place you regularly visit so you do not have to travel far out of your way.

 

Before leaving for your site:

  1. Make sure it’s safe and legal for you to access the river.

  2. Is someone going with you? We require that surveyors be accompanied when performing a survey and never survey alone. Let someone know where you’re going and when you’ll be back. 

  3. Do you have a charged mobile phone or way to call for help?

  4. Are you wearing the right footwear and clothing? Sturdy, waterproof footwear with good grip is best!

  5. Check the weather: you’ll need sun cream, a hat and some water in hot weather, several layers of clothing in cold weather – and waterproofs if it looks like it’s going to rain! Also consider whether recent heavy rain might have made river or riverbank conditions more dangerous.

  6. Check that you have all your water sampling equipment and that it is in good working order. 

The checklist for equipment is:

  • A TDS probe (also used for temperature)

  • A turbidity tube

  • Ammonia test strips

  • Nitrate test strips

  • Phosphorus test strips

  • Any other water quality testing equipment you may wish to use

  • You will also need to bring a bucket attached to some rope/string. We do not provide this.

 

 

 

When carrying out the survey: 

  1. Is the water level too high or fast to allow safe sampling? You can always just do the observational measurements. Even if you are sampling from a bridge, you may feel unsafe collecting a sample in high flows. NEVER sample during very high water levels or major flooding. If in any doubt don’t sample.

  2. Ensure that you do not disturb the riverbed when sampling as this will affect the sample result. Take your sample from surface waters.

  3. River water can contain harmful bacteria that can cause ill health and potentially serious diseases such as Weil’s disease (also known as Leptospirosis). For this reason – and for sample integrity – try to minimise personal contact with water to be tested. Use a suitable sample container (such as a small paint bucket on a rope) and wear nitrile gloves (or similar in you have an allergy). 

  4. Do not carry out sampling with open cuts or wounds and make sure to wash hands thoroughly between sampling and handling food or drink.

  5. Beware and actively avoid potential hazards such as traffic, livestock, slippery and steep banks, and only sample where and when it is safe to do so.

If you already have your own monitoring equipment, for example a hanna checker, you are welcome to use this instead but please note that use of your own equipment is at your own expense.

For those who complete training online, the kit will be distributed via a locker-based courier service or you can collect your kit from our office in Stowmarket.

If you are undertaking this monitoring as part of a group or organisation (e.g. Essex Wildlife Trust) then please ensure you abide by any health and safety requirements that they may have on top of our own.

OBSERVATIONS

You will be asked to make observations on the following basic information. Note: in cartographer, you can copy a previous survey so you do not have to fill out repeated details each time.

  • River Name

  • Location name (name of closest settlement, landmark etc.)

  • Location on a map (in the app, you can use your present location or select on the map)

  • Date and time

  • Access type i.e. public or private

  • Waterbody type

  • Land use around the site

  • Rainfall in previous 24 hours

  • You may add up to 4 photos

 

These guides can help with some of the observations you will be asked to make:

If you spot any sources of pollution that are causing damage to the environment, please contact the Environment Agency 24-hour incident hotline 0800 80 70 60. Pollution indicators include grey water discharge, oil, chemical or sewage odour, dead fish, or fish gasping for air.

You will also be asked for information about the physical characteristics of the waterbody. You can see our guide sheet for more information about river features and refer to the guides in the questions e.g. for sediment type. Depth and width should be estimated. Do not try and actively measure this as this could cause you to fall in.

 

That’s all the observations that you need to make on a survey. Remember only the observations are required, water quality is always optional and also remember to only perform observations on your first visit. 

WATER QUALITY TESTING

To perform water quality testing, you will need a safe riverside location and a bucket with string. Low bridges or solid banks make for the best places. Your container can either be a small bucket of the type purchasable from a hardware/DIY shop, or you can reuse a container such as a large round icecream tub. The container used should not be too large so that it is easily liftable when full of water without causing strain to either yourself or the rope. 

 

The container must only be used for water sampling to avoid contamination e.g. a normal gardening bucket will contain a small amount of soil that contains nitrate, phosphate etc. When collecting water, take great care and do not sample if the rivers flow is too strong or you do not have a good, safe footing. Collect water four times. The first three times, collect a less than full bucket, swirl this around to clean the bucket and dump the water back into the river. Then fill the container to an amount you can lift the final time. 

It is recommended that tests be carried out wearing disposable gloves and you must cover any cuts/abrasions etc. to avoid the risk of infection. 

 

Click each link for information on the respective tests. We recommend that you perform the tests in this order:

  1. TDS and Temperature

  2. Nitrates

  3. Ammonia

  4. Phosphates

  5. Turbidity

1. TEMPERATURE & TOTAL DISSOLVED SOLIDS (TDS)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


 

  • Switch on the TDS meter and remove the cap. Ensure the meter reads ‘0ppm’. If it shows oC or oF, press the ‘temp’ button until ‘0ppm shows’

  • Place the probe end of the meter into the water. Wait until the reading has stopped changing. This is the TDS reading. Remove the probe from the sample bucket

  • Press the ‘temp’ button until the meter shows oC. Place the probe end of the meter back in the sample.

  • Wait until the reading has stopped changing. This is the temperature reading. Do not record in oF

  • Switch off the TDS meter to conserve battery power

What is TDS?

Total Dissolved Solids (TDS) is a measure of the dissolved solid material within water that is generally smaller than 2 micrometres across. Common elements and compounds include calcium, nitrates, sodium, chloride, and potassium. It is roughly (though not directly) analogous to water hardness. TDS readings can be used to measure effects on the river such as where soil runoff is occurring. The levels of dissolved solids can have a great affect on the wildlife of rivers. Daphnia, for example, cannot survive in very high TDS conditions and young and spawning fish are sensitive to this too. Some of the major TDS components are also tested for with the other water quality tests of the ERW. A typical reading for freshwater will be less than 1000ppm. Please do not use the TDS meter in seawater as this contains TDS levels much higher than the probe can measure and can damage its calibration.

2. NITRATES

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

  • Remove a test strip from the container and replace the lid

  • Place the test strip in the sample for 2 seconds

  • Remove the strip and hold level and away from direct sunlight for 1 minute. Do not shake off any excess water

  • Hold the strip next to the guide on the container and identify which concentration it is most like

 

What are nitrates?

Nitrate is an ion (charged particle) with the formula NO3ˉ. Nitrates are compounds that contain this group (though it can also be found free floating). It is the main source of nitrogen for plants, used to make proteins and DNA. It is added to soils in the form of fertiliser. While vital for plant growth, in large quantities it can be harmful to people and animals. We would generally expect this to be bellow 30ppm. 50ppm is the safe limit for drinking tap water.

3. AMMONIA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


 

  • Remove a test strip from the container and replace the lid

  • Place the test strip in the sample for 5 seconds

  • Remove the strip and hold level for 1 minute. Do not shake off any excess water

  • Hold the strip next to the guide on the container and identify which concentration it is most like 

 

What is ammonia?

Ammonia, NH3, is a very common chemical. It is a very stable molecule with one nitrogen atom and three hydrogen atoms. It is a common waste product of organic processes in plants and animals, sewage treatment and the burning of fuels. It forms part of what the body is removing when you urinate. It is naturally a colourless gas with a distinctive, strong smell, similar to faecal matter. Salts of ammonia are sometimes used as fertilisers. Ammonia is, however, toxic to most animals, particularly fish and can change the pH of a river system. Ideal ammonia levels are bellow 0.5ppm.

4. PHOSPHATES

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


 

  • Fill the provided test tube to the 10ml level with sample water

  • Remove a test strip from the bottle and tightly close the lid

  • Bend, but do not fold, the strip in half, with the pads on the inside

  • Place this folded strip into the cap with the two small pads on one side and the larger pad on the other as shown here

  • Place the cap in to the test tube and slowly invert the tube 5 times, allowing the air bubble to travel from the top to the bottom and back again each time

  • Remove the cap and the test strip

  • Place the test tube on the white section of the chart provided. Look down through the tube and compare its colour to the chart. Record this as the colour it is closest to

 

What are phosphates?

Phosphate ions (charged particles) have the formula [PO4]³ˉ. It has a number of related, similar ions and forms salts and compounds with other ions. We group these all as phosphates. Phosphorus (P) is vital to all life, including use in some proteins, metabolic processes and in the enamel of bone and teeth. It occurs naturally in watercourses through organic processes, but can also enter the water through fertilisers and sewage. High levels of phosphates are detrimental to human and animal health and can lead to the eutrophication, a process where algae and other similar plants multiple to the point of blocking the light from a river system. Ideally, this should be bellow 100ppb.

5. TURBIDITY

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


  • Tip the contents of the sampling bucket into your turbidity tube slowly and carefully. It can be useful to have a second person assist you with this

  • When the tube is placed on a level surface, observe, from above, the Secchi disk (the black and white round sticker) at the bottom of the tube

  • Fill or empty the tube until you can only just see the disk, but it has not entirely disappeared. It can be a good idea to repeat your observation multiple times to be sure of the depth of water where the tube is and is not visible

  • When you are confident you have identified the depth the disk disappears at, check the scale on the side of the tube. The marking above the level observed is the turbidity score. If the water is so turbid that it is below the 240 mark when the disk disappears, record this as 240 and if the water is so clear it is above the 12 mark record this as 12

 

What is turbidity?

Turbidity is a measure of ‘cloudiness’ of a fluid (in this case, water). It is a measure of suspended material, most if not all of which is naked to the human eye as individual particles, but can be seen to make water more opaque. More turbid water blocks light from reaching aquatic plants and can also indicate pollutants.

READY TO GET RIVERWATCHING?

Find out how to sign up as an individual or register your local group

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