Officers at Arun District Council say unmapped services, including a surprise brick sewer, and rising construction costs have contributed to the overspend despite a search with a ‘ground penetrating radar’ and materials being ordered months in advance.
The original project budget was around £3.4 million but it is now expected to reach £5.3 million.
Members of the council’s Economy Committee approved a further £400,000 for the project at a meeting on Tuesday (July 26).
Director of growth Karl Roberts said the project was already making ‘quite a significant difference to the appearance of the town’, but the world from an economic point of view is ‘in a very different place’ from 12 months ago.
The newly approved funding includes £250,000 for overspends and £150,000 as a contingency.
Mr Roberts said future additional spending was ‘not anticipated’.
The major project is being brought forward in five phases with phases two and three currently underway along the High Street, Beach Road, East Street, and Clifton Road.
Since the project was approved, the council also agreed to stump up £240,000 for fibre broadband works that otherwise wouldn’t have been included.
Improvements from the rail station to the High Street (known as phase 1) have since been funded to the tune of £1.2 million by West Sussex County Council.
Councillors were pleased to see the progress but some noted that certain parts of the town are already ‘looking pretty mucky’.
Economy Committee chair Andy Cooper (Con, Angmering and Findon) said it had ‘given the whole town a lift’ but ‘wouldn’t look pristine forever’.
Mike Northeast (Lab, Courtwick with Toddington) said the dry weather meant there was no rain to wash dirt away from the lightly coloured paving.
He was reassured by Mr Roberts that pavements will be deep cleaned and ‘sealed’ – works that are included as part of the extra funding.
Opposition leader James Walsh (LDem, Beach) wanted to know that graffiti would be dealt with ‘swiftly’ and that trees would be cared for in hot weather.
Officers said Littlehampton Town Council had helped to clear some ‘unusual’ graffiti and increased tree watering is taking place.