Managing director Peter Brooks shrugged off the fall in pre-tax profit, saying the £18m figure for last year was exceptional, and insisted that Nuttall could still lay claim to being the pre-eminent civil engineer in Britain.
He said the firm was committed to setting an example of best practice in the sector and that every employee would hold a recognised qualification by the end of this year, up from the 58% target last year.
He said: "We have committed significant investment in terms of finance and human resources to the training of our workforce and subcontractors."
Brooks added that the firm was now concentrating on four main sectors: rail, road, water and environmental services.
The group had bought Finchpalm, a firm specialising in signalling, to develop services in the rail sector.
Brooks said renewed investment in roads would provide a good volume of tender opportunities, in addition to maintenance work.
The firm said the buoyant Irish market had led to Nuttall merging its operation there with its sister firm Ascon to focus on road work.