Budds Farm Wastewater Treatment Works

treats the wastewater from homes across

Portsmouth, Havant, Hayling Island,

Cosham, Paulsgrove, Waterlooville,

Horndean and Hambledon.

It serves nearly 410,000 people and duringnormal weather conditions treats almost109 million litres of wastewater per day,enough to fill nearly 47 Olympic-sizedswimming pools. During storm conditionsit can treat up to 200 million litres per day.

Historically, wastewater from Portsmouthwas released, untreated each day throughan outfall pipe into the sea at Eastney.

Havant’s wastewater was treated atBudds Farm and released directly intoLangstone Harbour.

Both these practices stopped in 2000 whenSouthern Water completed an environmentalimprovement programme to vastly improvewastewater treatment and improve thequality of the seawater off the Portsmouthcoastline and in Langstone Harbour.

Management of Wastewaterin Portsmouth and Havant

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Budds Farm was upgraded to receive andtreat the wastewater from Portsmouth.The flows from the city travel from EastneyPumping Station along a pipeline within a7.8km tunnel that runs beneath LangstoneHarbour to Budds Farm.

Here it combines with the flows fromHavant and Hayling Island and goesthrough a number of phases of treatmentbefore all the cleaned wastewater isreturned back along the tunnel to Eastneywhere it is released 5.7km out to seathrough a long sea outfall.

In 2007, Southern Water made furtherimprovements at Budds Farm to enhancethe wastewater treatment at the site.It is one of only two sites in the UKincorporating a four-stage BardenphoProcess for biological nutrient removal.The removal of nutrients such as nitrogenhelps to reduce algal blooms forming incoastal waters. These blooms may reducethe amount of oxygen in the water andcan smother other creatures, leading toa reduced food source for importantbirdlife in the harbour.

This level of treatment ensures the sitemeets stringent European Union legislationfor seawater quality.

The tunnel under construction between Eastney and Budds Farm

Biological treatment at Budds Farm

Stormwater ManagementDuring periods of heavy rainfall the flowsto Eastney and Budds Farm significantlyincrease when rainwater enters the sewers.

In Portsmouth in particular there are few‘surface water’ sewers so the rainwater andfoul water share the same pipes and all thewater will travel to Eastney Pumping Station.Flows arriving at the site can increasefrom 700 litres per second during dryweather to 20,000 litres per secondduring heavy rainfall.

Four storm tanks that hold a total of40 million litres of water are positionedunderground at Fort Cumberland to storestormwater during heavy rain. There arealso four storm tanks at Budds Farm thathold a further seven million litres ofstormwater. When the rain subsides,the contents of the tanks are sent tothe main works for treatment.

However, during prolonged heavy rainfalland periods of flash flooding, these tankscan fill up and there can be a need torelease water to avoid the sewer systembecoming overwhelmed and causing floodingof homes, businesses and the environment.

On such occasions water is released throughdesignated outfall pipes. These are pipesthat the Environment Agency has agreedthat Southern Water can use during stormconditions and emergency situations, torelease heavily diluted wastewater, generally99.98 per cent rainwater and 0.02 per centsewage, into the sea to prevent flooding.

These legal outfalls are monitored and localagencies are notified when they are used.

Within the Portsmouth and Havant systemthere are four main outfalls to preventflooding.

1 Eastney – the long sea outfall releasestreated wastewater and some stormwaterinto the Solent deep water channel.

2 Fort Cumberland – This outfall releasesstormwater into the sea at FortCumberland. Before it is released the wateris settled in the storm tanks, so the solidwaste sinks to the bottom. The highlydiluted stormwater then passes throughscreens that stop waste products, such asnappies, toilet tissue and sanitary products,from entering the sea.

The screens at Fort Cumberland weredamaged during a storm in 2010.A temporary solution has been put inplace but during severe weather theyare struggling to cope with the force ofthe flows. Southern Water is planninga £10 million scheme to provide apermanent solution at Fort Cumberland.

3 Langstone Harbour – This outfallreleases stormwater from the tanks atBudds Farm when they become full as aresult of heavy rainfall. The stormwater issettled and screened before it is released.

4 Langstone Harbour – There is a secondoutfall at Budds Farm that Southern Wateris permitted to use if Eastney PumpingStation is unable to cope with the volumeof treated wastewater returning to the sitefrom Budds Farm for release through thelong sea outfall. On such occasions,Southern Water is permitted to releasetreated wastewater directly from BuddsFarm into Langstone Harbour.

There is also an emergency outfall atBrockhampton Creek that Southern Wateris permitted to use if there is a seriousplant failure at Budds Farm.

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ConsentedStormwater

Outfall

EastneyPumpingStation

Long SeaOutfall

(5.7km)

L A N G S T O N EH A R B O U R

H A Y L I N GI S L A N D

P O R T S M O U T H

H A V A N T

Fort Cumberland

Budds FarmWastewaterTreatment

Works

Consented Outfall(treated

wastewater)

ConsentedStormwater

Outfall

Untreatedwastewater

Treatedwastewater

Tunnel

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1

2

4

3

There are many other outfalls around Langstone Harbour that are owned and operatedby other organisations and agencies, which are not the responsibility of Southern Water.

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Further investment to reduceflooding in PortsmouthRainwater and wastewater currently sharethe same sewers in Portsmouth and thesystem can become overloaded duringstorms. We will be building new sewersfor rainwater and pumping stations toensure that a significant amount isdirected straight out to sea rather thaninto the combined sewers. This will takethe pressure off the system and reducethe amount of water flowing to EastneyPumping Station during storms, reducingthe risk of flooding.

The £20 million scheme will take placein various locations across the citybetween 2012 and 2015. The work willbenefit the whole city, particularly areasthat have suffered flooding in the past.

New early warning technologyat EastneyDuring dry weather, flows at Eastneypumping station are pumped using electricpumps. However, in storm conditions,large diesel driven pumps are used toprovide extra pumping capacity at thesite and pump the additional flows.These pumps have to be warmed upbefore coming on stream and the startup process can take some time.

Southern Water is developing newtechnology that will provide a real timemonitoring and control system for EastneyPumping Station. The system will use:

• Weather forecasts providing advancedwarning of severe rainfall expectedin the area

• Monitors that will be positioned in theup-stream sewers to provide informationabout the volume of flows passingthrough them that will be linked directlyto the Eastney Control Room

• Permanent rain gauges positioned acrossthe Portsmouth area that are also linkedinto the system to provide informationabout rainfall levels

Together, this will provide a much moreaccurate prediction of the flows expectedat Eastney and when they will arrive, givingthe team on site advanced warning so theycan get the appropriate number of pumpsup and running ready to deal with theincreased flows.

Flooding in Eastney

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uthe

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Contact usFor further information please contact:

Customer Service CentreSouthern Water Southern House, Yeoman Road, Worthing BN13 3NX

Telephone:

0845 278 0845www.southernwater.co.uk

Please don’t pour fat, oil and grease

down sinks or toilets because this

accounts for about two-thirds

of sewer blockages.

Fat, oil and grease stick to theinside of drains and sewers.Over time, this hardens toform a concrete-like materialthat can block the entirepipe, causing flooding.

Please follow these simpleDos and Don’ts:

Fat causes floods

Fat deposits harden and stick tothe inside of drains and sewers

DO

• Wipe and scrape utensils and platesbefore washing and dispose of anywaste with your household rubbish

• Pour fat, oil and grease into a containerto harden and dispose of it with yourhousehold rubbish

DON’T

• Use hot water to rinse grease off potsand pans or surfaces

• Pour grease or fat down sinks or intotoilets