A blow to North Shore businesses could affect Auckland's whole economy

The Harbour Bridge will remain disabled for some time, while repairs are made to its superstructure.

Limited access to the North Shore is already said to be causing a drop in customer numbers and foot traffic.

Takapuna Beach Business Association's Terence Harpur says there are 43-thousand businesses on the North Shore.

He says the area is larger than Wellington or Christchurch - and makes up around 20 per cent of Auckland's GDP.