Stormwater project meets first major challenge

Southern Water’s giant stormwater storage tunnel at Brighton and Hove has

been hailed as a success by the Environment Agency.

Richard Hammond, environmental planning officer with the EA told WWT: “We

would have expected serious pollution problems with the old system this

summer. Instead, Hove beach met guideline standards under the EC Bathing

Water Directive and Brighton beach stayed within the mandatory limits.”

The tunnel, designed by Hyder Consulting, took the contractors five years to

complete and at a price of over £40 million dramatically exceeded the

original estimate of £30 million. It is now said to be performing a valuable

function.

Four primary dropshafts, along with a number of smaller shafts, now take the

storm overflow from Victorian interceptor sewers at Hove Street, Medina

Terrace, Norfolk Street and Grand Junction Road.

Previously, this waste poured straight into the sea, causing a serious

pollution hazard along a built-up area of coast popular with bathers.

Mr Hammond of the EA said: “Up until now, Southwick beach in Shoreham, west

of Brighton, has failed bathing water quality standards every year.”

Up to 132,000m3 of overflowing waste water from the town¹s sewers and drains

can be stored in the tunnel during heavy rain.

Once the storm waters subside, the wastewater is pumped from the eastern end

of the tunnel at Black Rock to Portabello sewage treatment works. Here it

is subjected to primary screening for sewage before discharge to sea.

However, there is still plenty of room for improvement, according to Mr

Hammond: “The long sea outfall does offer some protection, but secondary

treatment would make the system much more robust.” He pointed out that

although EA samples taken on a weekly basis show water to be safe inside the

200m zone, water further out could conceivably still be of a lower

standard.”

Taking this and other results into account, local pressure groups are

continuing to fight for secondary treatment.

Surfers Against Sewage (SAS) director Andrew Coleman said: “Despite the

tunnel, tests carried out by Brighton and Hove Council, which carries out

monitoring independently from the EA, show that water quality failed

microbiological standards on several occasions this year.”

Southern Water blamed four positive results for faecal coliforms in the

summer of 1998 on rogue builders connecting sewer pipes to surface drains,

which pour directly onto the beach.

In Southern Water’s defence, spokesman Graham Amy said: “It is inevitable

that other sources of pollution will become apparent after the building of

such a large project. If we find out who is responsible for this leak, we

will certainly be asking the council to take action.”

Commenting on the Council’s results, Mr Hammond of the EA spoke out in

support of the utility: “We are designated as the only competent authority

to assess beach standards. Having more than one monitoring scheme can cause

unnecessary confusion. On the whole, we are pleased with the progress

Southern Water is making in the area.”

He added “Under the EC Water Directive, secondary treatment facilities

should be installed for all coastal discharges by the year 2000.”

To get approval for a secondary treatment stage at Portabello STW, Southern

Water will still need to convince Sussex County Council that the development

will not damage the surrounding Area of Outstanding Natural Beauty (AONB).

The Council has already rejected Southern Water¹s first proposals for a new

treatment platform back in July. Reasons given included the large scale of

the installation, which the County Council said Œcould affect the local

geology’ and Œcontribute to the problem of heavy traffic’ in the Telscombe

Cliffs area.

Mike Elrick, of Southern Water’s technology group, said: “We are planning to

appeal against this decision. If the appeal is not successful by January

1999, we will be forced to consider siting the installation elsewhere.”

For the moment, Mr Coleman of SAS remains unimpressed with Southern Water’s

efforts: “I would be extremely surprised if Southern Water got their

application through on time to meet the 2000 deadline, as the tunnel itself

was over three years late.”

Mr Hammond said that discharge consent procedures were, at least, well under

way: “Southern Water’s application has just arrived on my desk. I am now in

a position to issue a licence with the requirement for secondary

treatment.”

However, he admitted that this alone would not be enough to guarantee

secondary treatment by the year 2000.

“If its planning applications are repeatedly turned down, Southern will be

entitled to apply for a special derogation under Section 8.1 of the UWWTD

(1991), to delay the installation of secondary treatment further.”