How does building a new bridge help encourage economic growth?

ppls can get across the river 2 work without getting their feet wet

It can increase economic growth as it's a form of investment. As a result, it acts as an asset to the community and therefore adds value to the local economy. So as investment is part of aggregate demand, aggregate demand will increase and therefore economic growth will increase.

yeah but how will i get across the river in my land car?

no one knows mate that's why the tories have us all swindled