Constructive waves have three main features:

• They are low in proportion to their length normally less than one metre high
•  They have a strong swash which carries material up the beach and have a weak backwash which doesn’t take the material away
•  They break gently, with only six and nine waves per minute.

Constructive waves allow material to be deposited along the coastline as material is slowly but constantly moved up the beach. This leads to the formation of features such as spits, tombolos and bars.