Just as an aside, the Dutch don't really do bicycle lanes, except on residential streets, or roads with low traffic volumes. On a road like this, where the maximum speed is either 80 or 100 km/h, there is almost always a bicycle path that is physically separated from the main roadway.
Wierd how the colour of the water is different for the two lakes, is there a way for boats to travel between them and how does the water colour stay separate if there is?
There are ship locks on both ends. But the water exchange is very little to change the color of the water. The green Markermeer is undeep and a little warmer than the IJsselmeer, algae flourish coloring the water green. Because the bottom of the Markermeer is of clay, there is a thick layer of slurry that is constantly stirred with every storm and does not settle. Waterplant growth is impossible. The water flowing into this lake is very limited but rich in nutrients, while the IJsselmeer is fed by the IJssel river in the southeast and flows to the northwest into the Waddenzee. There might be a solution to this problem, look at Markerwadden to see those plans.
They didn't do it because many people and environmental organizations were against the plans. In 2003 they officially decided to really not do it after years of postponing the plans.
The lakes that you're looking at were open sea a century ago. In the 1930s they built the Afsluitdijk (literally: the closing-off dyke), partly as a plan to get unemployed people to work, but also to deal with the flooding that the city of Amsterdam and other areas encountered regularly. Once this dyke was built, they started reclaiming a large part of the lake, the Noordoostpolder. This more or less finished during the war, in 1942. Later, they built an additional two polders, Oostelijk (Eastern) Flevoland and Zuidelijk (Southern) Flevoland, which together form the largest artificial island in the world. The Markerwaard was the next and final planned polder to be reclaimed. But it never happened - yet. The idea was to move Schiphol airport (reducing the amount of noise pollution, which I can attest is pretty serious because I lived right next to the busiest approach route for a while), and create extra land for agriculture. But Dutch agriculture is already ridiculously efficient, and produces much more than is needed for the country, while at the same time creating a lot of environmental issues. Reclaiming the land would also lead to a lower ground water level in existing areas, and the land wasn't needed for new cities. It was in the news a lot when I was young, but as already said by others, the plans kept getting postponed. Having said all that, the Netherlands is one of the most densely populated countries in Europe. Only Monaco and Malta have a higher population density. (On a side note: I live in Malta nowadays, and I laugh at any Dutchman complaining about overpopulation. There's oodles of space in the Netherlands, comparatively.) And I wouldn't exclude the possibility that, one day, another attempt will be made. The environment is taking a back seat in politics, what with populists and climate change deniers gaining more and more influence. Obviously, there would be grave risks associated with continuing the project. The Netherlands get all the water from two major European rivers (the Rhine and the Meuse), and any land that you reclaim reduces your capacity to store excess water. With sea levels rising, and potentially being higher than the lake(s), that's a serious concern. Unless, of course, you simply deny that there is such a problem, like the guy who won the general elections.
