Make the life easier
Having the bridge will help 20 families to access the main land easier. They can transport the product planted over there easily. They can save cost in transportation. For example, after bringing up Please be as detailed as possible. This answer should give the overall understanding of why a group should travel halfway across the globe to do this work! a cow, they sell it out and for whom staying at the island, the cost is also at bringing the cow over the bridge. Having a bridge also a help for people in main land go passby the island and more chance for business there
Make life safer
The bridge keep children and woman safe in the night and in the rain. Raining is time for mud road and slippery bridges. Such bamboo bridge is a challenge for walking across and many children and women has been witnessed to fall down to the canal. Night time is also a dangerous time as there is no light at all at the bridge.
Make the equality in social status
The people living is the island is considered poorer than in the main land, as only poor people choose to stay there. (if someone has more money, they choose to stay at mainland with higher price of property). A bridge will make island connected and the feeling higher-lower will be minimized. The bridge is also help business at main land go fast to bring a high income for people even at the island.