Northumberland visitor centre selects WPL package treatment

Aug 02, 2017

Wastewater treatment to meet highest environmental standards / Challenge of remote location overcome with HiPAF units / The Sill expected to attract 100,000 visitors a year

A prestigious new visitor centre in the heart of Northumberland National Park will benefit from a specially designed package plant from WPL. The Sill National Landscape Discovery Centre, a £14.2m joint project between the National Park and the Youth Hostel Association, is being built with the help of £8m from the Heritage Lottery Fund.

The centre, which overlooks a stretch of Hadrian’s Wall, is designed to open up the wild spaces of Northumberland to more people, including families, older people and people with disabilities.

Wild and beautiful

Stuart Evans, Sill Project Director of Northumberland National Park said, “The Sill will be much more than a visitor attraction – it will enable us to reconnect with our landscapes and our heritage. It is important that we seek the highest environmental standards in all our construction and operational activity to minimise disruption to the natural beauty of the area."

Dominic Hamblin, Technical Sales Manager at WPL said: “The Sill is a brand new building in a wild beautiful landscape, which is also next to the UNESCO World Heritage site of Hadrian’s Wall. The visitor centre is sited within the park where some of the highest quality river water in England flows. It was important to put together a package plant which met The Sill’s criteria.”

Visitors to The Sill are likely to number around 100,000 a year and there will be up to 30 staff on site as well as overnight lodgers at the integrated 86-bed hostel. The Sill, which will include a café, business hub, education and training facilities and a shop, is expected to be a year-round attraction, with visitors throughout the winter as well as during the summer months.

High environmental standards

WPL was asked to supply a package plant for 500 population equivalent, which could treat effluent to a standard of 20mg/l biological oxygen demand, 30mg/l suspended solids and 10mg/l ammonia.

Treated effluent at the site is released into a natural stream while sludge will be periodically tankered to an offsite wastewater treatment works. It was very important to supply back-up blowers and to enable the facility to connect a generator in the event of a power failure.

The architects originally intended the sewage treatment plant to stand in a natural valley alongside the centre. However, on the advice of installer Hutchinson Environmental Solutions, it was re-sited to a built-up plateau adjacent to the site when it became clear the access roads into the valley were too steep.

Dominic Hamblin said: “Within the industry WPL has a reputation for supplying bespoke plants which meet the precise needs of clients. With 25 years’ experience in manufacturing and designing plants WPL is known for its robust design and high standards.”

The package plant, manufactured by Hampshire-based WPL comprises two modular high performance aerated filter – HiPAF - units, a primary settlement tank to separate solids and a submerged aerated filter (SAF) tank for biological treatment. WPL will also supply an extra-large, glass-reinforced plastic control kiosk.

Back-up power

Installation by the contractor Hutchinson Environmental Solutions, on behalf of engineering company Sir Robert McAlpine Ltd, was completed in December 2016 and took only three weeks with installation time and health and safety concerns onsite are kept to a minimum.

The Sill is due to open to visitors in summer 2017 and is expected to provide a major economic boost to Northumberland by creating over 100 new jobs and attracting visitors spending some £5m extra in the local economy. The grant awarded by the lottery fund is the highest ever given to a National Park.

Hamblin said: “We have successfully partnered with Hutchinson Environmental Solutions throughout WPL’s 25-year history. Our complimentary skills consistently deliver high-end products and installations and The Sill is a great example of this.”

Peter Stedman, Operations Director for Hutchinson said: “WPL package treatment plants are very well made, with robust manufacturing and quality processes, which ensure continuous high performance and longevity. The back-up and support from the team is also something you don’t get from many companies.

“Those qualities give us confidence as an installation and maintenance company - confidence that we can pass on to the site owner.”

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