James Speck knew he had a job on his hands when the recession hit months after he took the reins at Kent Science Park.

Seven years later, he is about to retire as site director having seen employment at the business estate nearly double, attracting a big-money takeover this month by US private equity giants Angelo Gordon and UK property company Trinity Investment Management.

Despite the steepest economic downturn in a generation, the network of high-security labs and offices in Sittingbourne employs more than 1,650 people today, up from less than 900 people in 2008.

It is home to more than 60 companies, including firms like GW Pharmaceuticals and Novartis, which work in its 515,000sq ft of commercial space.

Its success prompted global real estate manager LaSalle Investment Management to reveal a 20-year masterplan for the site last summer, set to create 4,150 jobs, more than 300 homes and new facilities for Sittingbourne Football Club.

It might have been the ideal time for Mr Speck to bow out, until the plans were thrown into doubt as the site’s owner Mars Pension Fund put the park and four others up for sale for £95 million in December, under the advice of LaSalle.

Now its takeover is secured, the outgoing boss feels he has left the site in a healthy state, although there has been no announcement on the status of the masterplan.

“This is very much a time of change but there is not a question mark over the site,” said Mr Speck, 65, who is retiring after more than 30 years in property management.

“In the last seven years we have seen a real take-up in the facilities and in the last three to four years we have seen £85m of foreign direct investment in the park.

“We are talking about lots of small and medium-sized businesses doing that, which shows a great deal of confidence in the site – and in Kent.

“To me, that negates any question mark over the future of the park.”

Mr Speck admitted it was a “good question” whether the science park’s new owners would put the masterplan into action, although he feels the proposals have “huge potential”.

Yet the recent turmoil is small fry compared to the job he faced when he joined.

“The recession had a big impact on the plans for growth,” he said.

“We had to identify tenants who were in trouble to see how we could get them through it. At that time, tenant retention was as good as tenant growth.

“It was a pretty difficult time but at the same time, we identified some companies which had real strength.”

Mr Speck’s mission has been to make Kent Science Park a “location of choice” for companies moving to the county.

Part of this has been making sure it “appeals to the right people”, getting politicians on his side at local, county and parliamentary level.

He oversaw a visit by the Prime Minister in 2008.

“This is very much a time of change but there is not a question mark over the site...” - James Speck, Kent Science Park

“That is no mean feat,” said Mr Speck, who lives in Snodland. “When you are trying to attract big companies, that is a big coup.”

Mr Speck, a father of five and grandfather of one, began his property management career operating shopping centres before moving on to development.

His last job before joining the science park was the regeneration of Paddington station, where he was estates director.

He came to Kent Science Park “initially out of loyalty” to his previous employer LaSalle. After being given the opportunity to take a look at the site, it did not take him long to make a decision.

“It gave me this fascination,” said Mr Speck, who hopes to move to Holland in his retirement with his Dutch wife Yvonne. “It was a challenge I wanted to set myself up for.

“I had come from a development background working on new buildings and then I came to Kent Science Park with this long history.

“It was like an old lady and we have gone to great pains to revive her spirit and take her places.”