MC says the Moses project is causing a number of problems: a change in the tidal system, there's likely to be a change of the salinity in the exchange of fresh and seawater, and over time we've seen that algae and animals have started creeping in with unknown organisms. (What's there now that wasn't there four or five years ago?) Some algae and also mollusks and clams, and some fish which are more likely to be found in warmer weather. (This Moses project is this huge complex system with some air filled bladders that can break waves. It sounds good, but is this not positive?) It is not, the colonization from sea life on human manufacturers is very natural in the past, even ship wrecks have been colonized by marine life, so this is nothing new. But at the same time, we should not overshadow the bigger impact it's going to have. (What's the worst thing that's happening as a result?) This per se is not a big impact but it's a sign of larger changes that will last and rewrite the equilibrium of the marine life of the Venice lagoon. (But are not these barriers necessary for people in Venice?) That kind of fixed infrastructure model is not the solution for Venice. It's a temporary act, although of a permanent nature in terms of effect, and there were other solutions that were less costly but more complex to set up and plan.