Like Coldfire noted, it does, yeah. It really is a last-ditch defense. However it appears to recover eventually.
Also at least in 1672, we’re not talking a huge chunk of the country and it appears that some of the water released was fresh(ish) from the Netherlands rivers ( or at least the Waal and Lek ). So a quick quote ( emphasis added ):
*Holland was saved, initially, by sheer luck, and subsequently by effectively innudating the stretch of terrain, the so-called water-line, running from Muiden, in front of Amsterdam, on the Zuider Zee, via Bodegraven, ( where the Prince established his headquarters ), and Schoohoven, to Gorcum on the Waal…
…Over the next fortnight the French could have still crossed the ‘water-line’; for although the dikes and sluices were opened - after some resistance, particularly around Gorcum, from armed peasants reluctant to see their land ruined - the water level rose only slowly owing to the dry summer months.*
From the book I cited earlier in this thread.
If you look at a map, you’ll see that this is roughly rectangular chunk of land in the central Netherlands, cutting Holland off from Brabant and Geldre to the south and east. From the context above, I would also assume that the ‘dry summer months’ comment refer to the low-level of the rivers, as such would obviously have less of an impact on the sea-level. And note the armed opposition to the loss of farmland.
So it was a drastic tactic. But it worked :).
The_Stranger: No worries :).