WATERBUS: A model to estimate boats’ emissions in “water cities”

•The WATERBUS model has been designed to estimate boats emissions in the “water cities”.•Lagoon boats emissions can affect Venice environment.•Pollutants abatement effects of a new generations engine are positive.

An emissions factor model (WATERBUS) is developed to estimate boats emissions in Venice, Italy. Waterbuses and small private boats undertake most of the internal transport with the city and provide connections with other islands in the Venice lagoon and the mainland. Even though the engines of these boats are smaller, sailing conditions do not correspond to those of larger vessels. Consequently, emission factors typically associated with large boats are not readily transferrable. We thus estimate specific emissions for small boats and waterbus in the lagoon area. The WATERBUS model is used to assess emission changes that would occur if the fleet were fitted with electronic engines.