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www.RiverBollin.info

River Bollin Information

What needs improvement, and what is being done?

This unofficial page is compiled and maintained by Colin Townend.
Please advise any errors, omissions, and suggested additions.

Join the Friends of the River Bollin Facebook Group

The Old Mill Lane Weir, Macclesfield (Updates every minute) Location

Introduction

When huge amounts of foam appeared in the river in February 2023, it was the trigger to explore what was happening in the Bollin, and it turns out a lot of people are working hard to improve the river:-

• The biggest single improvement to water quality in the Bollin will be at the start of 2025 when £50m of improvements at the Prestbury waste water treatment works, that serves Macclesfield and Bollington, come onstream. This provides enlarged storm surge storage tank capacity and a new treatment process that will reduce the levels of Phosphorus and Ammonia entering the river to 0.3mg/l and 2mg/l respectively.
  

  Details as of May 2023   UU video update March 2024 Site Visit and Process Explanation 20th March 2024



• The next job is to introduce storm surge storage tank for the area's worst performing CSO (Combined Sewer Overflow) on Westminster Road, which discharges into the Bollin. This is likely to include work to divert some surface water from the combined sewer, and to build a new storm surge storage tank.


• United Utilities have published a map for your phone, showing the state of their CSOs in 'near real time', so you can keep dogs and children out of the river at appropriate times. Link to  their Map
.
• Water UK have published a CSO map for the whole of the UK here. (Their 'My Location' button is only visible in landscape mode on some phones.)


• United Utilities have recruited and trained River Rangers to patrol and troubleshoot the river. Details


• The Mersey Rivers Trust hold regular meetings of BEACON, a group of organisations with an interest in improving the river quality of the Bollin. 
  These include United Utilities, the Environment Agency, the National Trust, local government, fishing clubs, and other community groups.


• The Mersey Rivers Trust itself has people working on reducing Invasive Non-Native Species (INNS), reducing flood risk, and liaising with farmers to reduce their contribution to toxicity in the river.


• And of course, many members of the public are involved. How to Help


• United Utilities are offering grants up to £2,500 to community groups working on improving river quality. Details

Pollution Reporting

The Environment Agency says that over a thousand fish were killed on 22nd of February 2023 after a foaming agent found its way into a surface water drain that fed into the river near Lyme Green. (EA Ref: 02132393)

The agency subsequently found some misconnection of foul water into the surface water drainage system, and corrective action has now been completed.  The agency separately took action to prevent bad practices.

But this was only one of a series of pollution events dating from December 2021 to May 2024.

See our Blog of Pollution Events

If you see any new pollution, note the location and phone it in right away, so that it can be investigated before it disperses.

Put these numbers in your phone's contacts.

Get this map on your phone If you have time to trace the pollution upstream to where it enters the river, this map shows places where you can see the river from the road

The What 3 Words App is a good way to define the location. Use its 'photo mode' to share a photo and the location in one image.

If you take a photo, your phone probably records the location, and you can see it by pressing the 'i' or menu button while displaying the photo.

Read the two-page document from the Environment Agency:- Link

Why is man-made foam bad for the river?

Foam is an indicator of the presence of detergents. Detergents can contain phosphates used as a water softener to make washing more effective, but phosphates also act as a fertiliser, promoting excessive algal grow in water courses, which in turn can starve other river life of oxygen.

The other major ingredients of detergents are surfactants (surface active agents) which break down surface tension, allowing water to 'wet' surfaces more uniformly and to seep into the fibres of dirty clothes.
One end of their molecule is attracted to water and the other end attracted to dirt and grease, so they help water get hold of grease, break it up, and wash it away.

But surfactants may also attack the natural oils in the mucus membranes of fish, stopping their gills from working properly, and increasing their risk of attack from other chemicals in the water. Some surfactant ingredients (including one called nonylphenol ethoxylate or NPE) produce what are called endocrine-disruptors, which can affect the hormonal balance of animals (including humans).

Although surfactants can be toxic to fish and other aquatic life, most surfactants biodegrade relatively quickly in sewage treatment plants before they can do much harm to the natural world.

Sewers and Drains

Drains are NOT all the same!

Whilst 'foul water' from toilets, sinks, showers, and baths is directed to a water treatment plant via the sewerage system, 'surface water', rainwater from roofs, hard standings, and roadside storm gulleys, is sent directly to rivers and eventually the sea.

So try to avoid putting anything down a surface water drain, other than clean water.

If you have to dispose of some watery liquid, you should use the kitchen sink drain, not the rainwater drain.

Oil and paint can be disposed of safely at the local tip (Household Waste Recycling Centre).

Incidentally, washing machines are responsible for 35% of misconnections, when the outlet is wrongly directed into a rain water drain. This risks sending soapy water, and microfibres from synthetic fabrics, towards a river.

The water treatment plants clean up the sewage and feed it into the river. The performance standards for these plants have been raised recently and a lot of investment is in process. Read about Macclesfield Waste Water Treatment Works

  In some areas the two drain types are joined into a 'combined sewer'. These are vulnerable to being overwhelmed in very heavy rainfall, and vulnerable to blockages restricting the system's ability to absorb the incoming flows.

To avoid risk of sewage back-ups, combined sewers are protected by 'Combined Sewer Overflows' (CSOs). This 'protection' is achieved at the expense of watercourses, and the map below shows several CSOs as the river wends northwards through Macclesfield.

It is worth reporting any CSOs that are discharging at times when there was no recent heavy rainfall. There is a 'nearly live' status map of CSOs.

At its simplest, a CSO works as shown below. Heavy rain or a blockage can cause the sewage level to rise above the dam level.

Combined Sewer: Wikipedia

CSO discharges are typically minimised by diverting some surface water out of the combined sewer, or by building storm surge tanks up-stream.
These tanks are kept empty until heavy rainfall starts to overwhelm the system.
Then, flow is diverted into the tank to be fed onwards to the water treatment works after the incoming flow has abated, and the system can cope once more.

How did we come to have Combined Sewers?
Read the story

You can help by not flushing those items that increase the risk of sewer blockages - the other main cause of CSO discharges.

If you see a problem with a CSO, make a note of the precise location using the What 3 Words App, or note the Permit Number from the map below, and call The Environment Agency on 0800 80 70 60

The 2023 data for our local CSO's is shown on the 'Top of the Poops' website supported by Surfers Against Sewage :-

The Rivers Trust also provide a very detailed drill down into sewage outlets, and Macclesfield's worst performing CSO is at Westminster Road:-

Click on the map to explore other CSOs.

In September 2023 the Environment Agency issued an updated Storm Overflows Reduction Plan, placing obligations on the water companies.

On 1st May 2024 United Utilities published a 'nearly live' map of storm overflow status. Amongst other things this should inform people before allowing their dogs or children to bathe in the river at places such as Riverside Park in Macclesfield.

The Westminster Road overflow improvement design work is in progress by United Utilities.

These CSO maps are available for other water companies too here

 Farm Run-off

Water companies get all the headlines about river pollution, but long stretches of rivers pass through farmland, and nationally, farms are a greater source of poor river water quality. source

Nationally, poor management of manure and slurry in rural areas is the agricultural activity that has the greatest impact, affecting 36% of all river water bodies.
Poor livestock management affects 28%.

The government has issued regulations known as ‘The Farming Rules for Water’ to reduce river pollution. This is a brief summary:-

Fertilisers

• The use of fertilisers must be justifiable, and not happen when it is most likely to run off into rivers; when the ground is frozen, snow covered, or water-logged.

• Slurry is considered to have a high content of Readily Available Nitrogen (RAN) and should not be spread in autumn and winter, when it is less likely to be absorbed by fast growing plants - and therefore prone to run off.

• Manure has a low RAN and is not restricted for timing, but should not be applied within 10m of a watercourse – unless ‘precision equipment’ is used, in which case 6m.

• Manufactured fertilisers can be applied up to 2m from a watercourse.

• Organic manure should not be stored within 50m of a watercourse, and livestock feeders where animals congregate should be more than 10m away.

• Silage liquor is one of the most polluting of farm-based products.
  

Erosion - Precautions to prevent soil erosion (taking nutrients into the watercourse):

• For example, the direction of ploughed furrows should be across the slope, and large areas of bare earth should be avoided.

• Livestock should be kept at least 5m from a riverbank at times when their hooves would break up the ground and promote erosion.

• It is best if water troughs are provided, so the river is not the source of drinking water.

• Farm yards and buildings sometimes direct rainwater into a slurry pit. This can cause the pit to fill and need emptying at inappropriate times of the year:-

The Rivers Trust have a more detailed resource: Water Friendly Farming Hub

 How to Help

	Report any pollution you see 0800 80 70 60
	Volunteer with Bollin Valley Rangers and Mersey Rivers Trust
	Know what should NOT go down your toilet
	Don't flush ANY wet wipes. We used to be told that 'Fine to Flush' wipes were OK to go down the toilet, but in February 2024 Water UK abandoned the scheme, acknowledging that wet wipes are overwhelmingly the main cause of sewer blockages. More
	Install a Water Butt It will delay storm water getting into the drains, giving time for the system to cope, and it will save money on your water bill.
	Retain microfibres from your washing machine or at least ask:- 'How often do your synthetic clothes REALLY need washing?'
	Keep fat and cooking oil out of your drains. Put cooking oil in a sealed container in your black bin. It will then be burned for energy recovery by Cheshire East.
	Trolleywise has an online trolley reporting App. If you give them the location using the What 3 Words App on your phone, they will fish abandoned trolleys out of the river. (Neither Tesco, nor the Council provide this service).
	Report Blue-Green Algal Blooms using the App on your phone
	If you are interested in the general reduction of single-use plastics getting into the sea, visit www.notjustonce.org
	INNS Mapper is a website and phone App that facilitates the reporting and identification of some 62 invasive non-native species; both living on the banks and swimming in the water of our rivers.
	Are your drains connected correctly? Washing machines are responsible for 35% of misconnections, when the outlet is wrongly directed into a rain water drain.
	Clearing litter from the streets and river banks avoids plastic getting into the river. There are local groups that organise litter picks:- The Bollin Valley Partnership Tel: 01625 374790, Emma.houghton@cheshireeast.gov.uk Prestbury litter picking group meet on the first Saturday of the month at St Peter's Church, and sometimes target the banks of the Bollin. Contact: Carol Waters carolannbutterfly@gmail.com Macclesfield Litter Picking Macclesfield Town Council and ANSA have agreed that litter pickers can leave green litter bags next to public litter bins for collection by ANSA. (Green bags are suggested so they know it is not fly-tipping).  The green bags can be requested via email from ANSA by emailing Caroline.Griffies@ansa.co.uk and they will deliver them to your home.
TV Programmes to Watch

Who is Involved?

	The Environment Agency is keen to investigate any concerns about river pollution raised by the public, but they can only investigate while the problem persists, so prompt reporting is essential:- 0800 80 70 60 website
	The Bollin Valley Partnership manages the Riverside Park off Beech Lane, and organises a series of conservation events. www.bollinvalley.org.uk Tel: 01625 374790 Emma.houghton@cheshireeast.gov.uk
	Healthy rivers for people and wildlife www.merseyrivers.org The Mersey Rivers Trust works on reducing Invasive Non-Native Species (INNS), reducing flood risk, and liaising with farmers to reduce their contribution to toxicity in the river. Follow them on Facebook for news of working parties.
	BEACON (Bollin Environmental Action and Conservation) (BEACON includes representation by United Utilities and the Environment Agency) The latest version of the BEACON Action Plan can be downloaded here and a progress update can be downloaded here.
	Waste Water Pollution of Rivers United Utilities have recently appointed River Rangers to attend incidents riverrangers@uuplc.co.uk Action Plan for Macclesfield Forest
	The Friends of the Bowdon Bollin (FOBB) was formed in 2007 to safeguard local countryside footpaths in the Bowdon Bollin Valley. They have carried out many projects and rely on local residents volunteering to help with eradication of non-native species, litter picking, path improvements, funding and publicity.  Website

Fishing Groups

Mottram St Andrew Fly Fishing Club

Macclesfield Fly Fishers Club

Bollin and Burkin
Fly Fishers

Lots of informative videos about river improvement

River Facts and Figures

Department for Environment: Bollin Source to Dean:-

https://environment.data.gov.uk/catchment-planning/WaterBody/GB112069061320

(A mind-boggling array of layers to select and filters to apply):- Index

Live Bollin Water Level Monitoring:

 Old Mill Lane Macclesfield Prestbury   Wilmslow

The Wild Trout Trust Fishing Assessment Sept 2020

If you want to trace any pollution upstream, the map below shows where the river can be seen from the roadside marked in red, and CSOs are marked in yellow.

Click anywhere to zoom in.

Get this map on your phone

Surveying Methods

If your survey reveals pH below 6 or above 8, or an Ammonia reading above 3.0 ppm,
or any pollution incidents:
  Report them to the Environment Agency Clean Stream Team on 0800 807060.

River Jargon

The water industry and river ecologists have their own vocabulary:-



There are a lot of jargon words used in the water 'world'. Many are listed below, but it is useful to start by knowing the basic waste water treatment process,
and the simplest explanation I have found is here from the US.

• Activated - refers to 'good' bacteria in a water treatment plant being 'activated' by bubbling air through the material to give extra oxygen to promote growth.

• AGS - Activated Granular Sludge - a waste water treatment process. Aerobic granules are a type of sludge that can self-immobilize flocs and microorganisms into spherical and strong compact structures. The advantages of aerobic granular sludge are excellent settleability, high biomass retention, simultaneous nutrient removal and tolerance to toxicity. Explanatory video

• Algal bloom – an uncontrolled increase in the growth of bacteria or algae often caused by eutrophication.

• Ammonia – a toxic compound that dissolves in water to form the ammonium ion. It is an animal/human waste product and used in fertilisers.

• AMP7 – United Utilities Asset Management Plan for 2020-25. AMP8 = 2025-30

• BAFF - Biological Aerated Flooded Filter. Utilises buoyant plastic bead media for wastewater treatment. There is an inherent risk of plastic loss to the environment given the media floats and can be gradually abraded over time, releasing micro-plastics into the river discharge.

• BEACON (Bollin Environmental Action and Conservation) was set up 14 years ago to control and manage invasive non-native species within the Bollin Catchment; subsequently its concerns have expanded into water quality and catchment issues. Its Steering Group comprises a wide range of partners from the voluntary, private and statutory sectors. A priority for BEACON is working with community groups and volunteers. BEACON is part of Mersey Rivers Trust.

• Biochemical Oxygen Demand – the amount of oxygen required by aerobic microbes to break down the organic material in a sample of water. The breakdown of organic material removes oxygen from the water.

• Biofilm - In waste water treatment, good bacteria form a film coating on a substrate. This substrate may be a flat sheet, or honeycomb sectioned plastic chips, gravel, or most recently organic granules in the MOB process.

• BNR - biological nutrient removal - a waste water treatment process.

• BOD - Biological Oxygen Demand - a measure of how many oxygen-hungry organisms are present in the water. Sewage plant input is typically around 200mg/litre input; output should be no more than 30mg/litre

• Bowser – a mobile tank that is often used to transport water.

• CaBa -The Government introduced the Catchment-Based Approach (CaBA) for the management of the water environment across all areas of England for more integrated water management, by establishing catchment partnerships which work together with local stakeholders to deliver improved water quality through River Basin Management Plans and to reduce flood risk.

• CaST - Catchment Systems Thinking is United Utilities’ approach to managing catchments in a holistic, integrated manner. Link

• Catchment Monitoring Cooperative - led by The Rivers Trust and United Utilities, aims to combine river water quality data in a local collaborative evidence base. This will allow data collected through citizen science and community monitoring to contribute to evidence-based integrated catchment management. The Upper Mersey has been selected as one of eight demonstrator catchments to develop and implement the proposal.
  Furthermore, funded through the Green Recovery Challenge Fund, Mersey Rivers Trust has trained 11 volunteers as River Guardians in the Bollin catchment. These volunteers undertake monthly water quality sampling and kick sample surveying of aquatic invertebrates at priority locations along the River Bollin and its tributaries.

• Category 1,2,3,4 Environment Agency pollution event classifications - are divided according to the 'impact or effect on the environment, people and/or property, or on EA operations' as follows:- 1 = Major, serious, persistent and/or extensive; 2 = Significant, 3 = Minor or minimal, 4 = Substantiated incident with no impact.

• Chalk Streams - rise from springs in landscapes with chalk bedrock. Since chalk is permeable, water percolates easily through the ground to the water table and chalk streams therefore receive little surface runoff. As a result, the water in the streams contains little organic matter and sediment and is generally very clear.

• Citizen Science - activity that involves the public in scientific research and thus has the potential to bring together science, policy makers, and society as a whole in an impactful way.

• Combined sewer / drain – a combined foul and surface sewer. Designed to transport toilet waste, waste effluent and rain water to sewage treatment works.

• CSO- Combined Sewer Overflow, a particular problem in the Northwest where 54% of sewers combined vs. national average 33%, compounded by annual rainfall 28% higher than England and Wales average.

• Diffuse pollution – pollution that does not have a single entry point into a watercourse. It also covers pollution that originates within surface sewers, that has a single discharge point (the outfall) and a diffused source or sources within the sewer catchment (diffused point source pollution).

• Drinking Water Safeguard Zones (SgZs) are established to reduce and prevent pollution of water abstracted for drinking water supplies. Safeguard Zone Action Plans set out actions to prevent and avoid water quality deterioration. See Map

• EDM - Event Duration Monitoring of sewer spills. See Bollin Data

• Effluent – treated or untreated waste water, such as foul sewage or grey water. Also covers waste water from industrial processes.

• Electrofishing - involves creating an electric field in the water that temporarily immobilises the fish or influences the direction in which they swim, making them relatively easy to capture with a net. Details

• EPSs are mostly composed of polysaccharides (exopolysaccharides) and proteins, but include other macromolecules such as DNA, lipids and humic substances. EPSs are the construction material of bacterial settlements and either remain attached to the cell's outer surface, or are secreted into its growth medium. These compounds are important in biofilm formation and cells' attachment to surfaces. EPSs constitute 50% to 90% of a biofilm's total organic matter

• Eutrophication – the process responding to excessive levels of nutrients, such as nitrates and phosphates from fertilisers or sewage. High levels, cause rapid growth of algae and plants. These smother water courses and result in low oxygen levels, killing off the wildlife, most often observed as algal blooms in warm weather.

• Fatbergs are formed when fat, oil and grease are poured down sinks and drains and combine with items that should not be flushed down the toilet, such as unflushable wet wipes, nappies and cotton buds. In 22019 a 40 ton 'berg was found in London.

• FBBR - Fixed bed biofilm reactor - video

• Ferric Sulphate - sometimes used to precipitate out phosphates before treated water is returned to the river.

• Foul sewer / drain – drains and pipes designed to transport toilet waste and waste effluent to sewage treatment works.

• Humus settlement tanks - are often the final settlement stage in waste water treatment processes.

• Grey water – waste water from sources such as washing machines, sinks and dishwashers.

• IBC – Intermediate Bulk Container made of plastic with a metal cage that holds approximately 1000 litres.

• IFAS - Integrated Fixed-film Activated Sludge. more

• Impermeable – does not allow substances, such as water, to pass through. Iridescence – rainbow effect caused by thin layers of oil on water.

• INNS – Invasive, Non-Native Species, includes Himalayan Balsam, Japanese Knotweed and Giant Hogweed, along with Killer Shrimp, Signal Crayfish and American Mink. more details

• Kick Sampling -is a method for collecting invertebrates from shallow waters by agitating the stones or sediment of a river or stream by foot and catching the sample in a sturdy hand net that is held downstream.

• Leaky Dam – a barrier constructed to delay flash flood water to ease flooding downstream.

• MBBR - Moving Bed Bio-film Reactor more

• Misconnection – a connection to a sewer that results in wrong disposal taking place, such as a toilet to surface sewer.

• MOB Technology - Mobile Organic Biofilm water treatment being deployed at Macclesfield’s Prestbury WwTW, offering tighter ammonia and phosphorus permit limits and providing additional capacity to meet the need of forecast increases in population.

• NFM - Natural Flood Management, leaky dams etc.

• Nitrate Vulnerable Zones - see NVZ

• Nitrogen - Agriculture is the dominant source of nitrate in water (about 70% of total inputs), with sewage effluent a secondary contributor (25-30%) nationally. 55% of England is designated as a Nitrate Vulnerable Zone (NVZ) due primarily to elevated nitrate concentrations (above 30mg per litre) in groundwater and rivers, and to a lesser degree because of eutrophication (See above) of estuaries and lakes/reservoirs. NVZ action programmes to reduce agricultural nitrate pollution have been in place since the late 1990s. 

• NVZs - areas designated as being at risk from agricultural nitrate pollution.  If your land is in an NVZ you MUST follow a mandatory set of rules which require the careful management of nitrogen fertiliser and organic manure.
  See Map

• Oil interceptor – usually a series of tanks designed to remove oil from water by slowing the flow rate and allowing the oil to separate and float on top of the water.

• PAOs - Polyphosphate Accumulating Organisms are purposely enriched in treatment plants to remove Phosphate from wastewater. PAOs release P under anaerobic conditions, but take up more than they released if subsequently put under aerobic conditions.

• Phosphate –  concentrations above 0.1mg per litre can promote eutrophication. (See above)

• Poaching - the damage caused to turf or sward by the feet of livestock. Hooves cause compaction of the soil surface, leaving depressions which can be 10cm to 12cm deep. This can form an almost continuous layer of grey anaerobic soil, where natural activity, carried out by soil micro-organisms, is low.

• Redds - depressions in the river bed excavated by trout and salmon to lay eggs. Can be damaged by cattle drinking in the river. more info .

• RFD - Reasons For Deterioration in water test results

• Riparian - relating to or situated on the banks of a river.

• RNAGs – Reasons for Not Achieving Good Status in respect of the WFD (see later).

• Septic Tank - A compartmentalised settling tank that provides conditions for settlement and anaerobic breakdown of solids from wastewater.

• Sewage or Sewerage? - Sewerage is the infrastructure of sewers that transports the material sewage.

• Sewage – contaminated toilet water containing human waste.

• Sewage Farm - the original name for sewage treatment, from a time when areas of land were reserved for the spreading or spraying of sewage for natural decomposition.

• Sewage Fungus – bacteria that grow in response to increased nutrient levels from sources such as sewage, often forming ‘hairy’ mats on the bottom of watercourses.

• Sewage treatment works – a place that removes physical, chemical and biological contaminants from water before returning it to a river.

• SgZs - Safeguard Zone Action Plans aim to reduce and prevent pollution of drinking water supplies. See Map

• Siltex - Finely milled chalk used to reduce organic silt in ponds, lakes and rivers. more

• SSO - Storm Sewage Overflow. See also CSO.

• SuDS - Sustainable Drainage Systems are designed to manage storm water locally (as close its source as possible), to mimic natural drainage and encourage its infiltration, attenuation and passive treatment.

• Surface sewer / drain – drains and pipes designed to transport water caused by rainfall to watercourses.

• TSS - Total Suspended Solids - measured after passing a 0.45 micron filter. Typically 200mg/litre input and 30mg/litre output required.

• UMCP - Upper Mersey Catchment Partnership

• Water UK - The trade association for UK water companies.

• Watercourse – any flowing body of water, such as a brook, river, pond or lake. It also covers canals and even dry ditches that carry rain water to a flowing body of water.

• WEIF - Water Environment Investment Fund financed by the Environment Agency.

• WFD – The Water Framework Directive set out rules to halt deterioration in the status of EU water bodies and achieve good status for Europe’s rivers, lakes and groundwater. Now adopted in the UK too.

• WINEP - Water Industry National Environment Programme, the Programme of works that water companies must deliver to meet their obligations under environmental legislation and UK Government Policy.

• WwTW – Waste water treatment works.

• Yellow Fish - a simple pollution prevention tool with the clear message: ‘Only rain down the drain!’ You can help to protect your rivers by stopping pollution incidents. Details and here and here