It's an interesting article, but a better title would be "How the Netherlands were dredged without fossil fuels". The article makes note of how wind power was

It's an interesting article, but a better title would be "How the Netherlands were dredged without fossil fuels". The article makes note of how wind power was used pre-electricification at several points (windmills, specialized sailboats) so they're not oblivious to that obvious answer. Since it can be periodic and during daytime surely electric dredgers with umbilicals could do some of the heavy pumping based off a wind and solar powered grid. Would be interesting to see the dredging power requirements vs local renewable resources.