A LEGACY of the region's industrial past is set to hit plans for the opening of the region's largest bird reserve.

The Royal Society for the Protection of Birds and their appointed contractors were aware of some of the hidden secrets of the derelict site, earmarked for a 1,000-acre bird reserve.

But construction teams working on the site of the former ICI Saltholme trial farms, adjacent to the Seal Sands petro chemical complex, have encountered surprise pitfalls - including two full slurry pits, buried asbestos and acres of crumbling concrete foundations.

Dealing with those hazards will delay the official opening of the £6.8m wildlife haven - the North's largest wetland wildlife reserve.

It was initially hoped to open the RSPB flagship Saltholme reserve in August next year, but the site, which lies between Billingham and Seaton Carew, now looks set to be officially launched in the spring of 2009, although most of it will be open to visitors from next autumn.

While the multi-million pound wild bird discovery visitor centre, encompassing an education centre, shop and cafe will open for business next autumn, work will have to continue in other areas of the reserve.

Project Manager Kevin Bayes told The Northern Echo: "The intention was that the reserve would open in the autumn of 2008, but we have run into a number of issues we have had to deal with, including contaminated land.

"We have had to take a lot of asbestos from under 20 years of bramble growth. We also came across two huge slurry pits. We knew about the foundation slabs, but we will be crunching concrete for the next three weeks. We are recycling the crumbled concrete under the car parks."

He added: "I think what we will be doing is a soft opening in the autumn, with the wild bird discovery centre, shop and café open, and a big launch in March 2009."

The long-defunct, but controversial Teesside Development Corporation (TDC) came up with the idea of a 3,000 acre reserve in the early Eighties, but, like several other TDC projects, it did not progress from being an idea.

The present scheme for a world-class bird reserve came into flower with a partnership between the Teesside Environmental Trust and the RSPB, at the beginning of the new millennium.

"We have looked very long and hard at how we can make it exciting to people," said Mr Bayes. "The reserve will cater for ardent bird watchers and those nature watchers who have been inspired by the waves of television's eco broadcasts, including Spring Watch and Hands on Nature, to leave their armchairs and explore what is on their own doorsteps."

Mr Bayes said of the reserve, its surrounding skyline dotted with storage containers, refinery chimneys and stacks: "It's pretty unusual and unique in the North of England. You stand in the middle of the site and look at the skyline. I think it will be part of the draw of the place. You have this incredible inter-mix of industry and wildlife.

"Industry in the past has been destructive of habitat, yet it is only because of industry that Saltholme exists. Now it is all about co-operation and awareness.'' The RSPB confidently predict that, when finished, the reserve will attract more than 100,000 visitors a year to the reserve on which new pools are being created, tracks, hides and walkways installed.

Three hides are planned initially, with the main Saltholme hide offering a 360 degree view of wildlife pools and having a living roof of vegetation, and access to it screened by mounds to avoid disruption to the birds.

Existing pools are already visited by migrants from Siberia and the US, with impressive wader numbers. Last summer, it had the largest mainland common tern colony. It is anticipated the 20 hectares of reedbeds will attract marsh harrier, bittern and bearded tit.