Around the year 1,200, the Hollandse IJssel was a tributary of the Lek River that started at Het Klaphek in IJsselstein. At the spot where the winter dyke has two prominent kinks, the Hollandse IJssel was dammed up in 1285-1289. The areas around this river had suffered so severe flooding in the centuries before that only one solution seemed the best. The Dutch count Floris V was powerful enough to cut the knot and the supply of river water from the Lek was stopped with a huge dam. Henceforth, the Lek carried all the water from the Rhine towards the sea. The Hollandse IJssel became a tidal river with one inlet and outlet opening at IJsselmonde (Rotterdam). Around 1500, there were already voices calling for the IJsseldam to be replaced by sluices, as the Hollandse IJssel was becoming seriously
closing ...
Around the year 1,200, the Hollandse IJssel was a tributary of the Lek River that started at Het Klaphek in IJsselstein. At the spot where the winter dyke has two prominent kinks, the Hollandse IJssel was dammed up in 1285-1289. The areas around this river had suffered so severe flooding in the centuries before that only one solution seemed the best. The Dutch count Floris V was powerful enough to cut the knot and the flow of river water from the Lek was stopped with a huge dam. Henceforth, the Lek carried all the water from the Rhine towards the sea. The Hollandse IJssel became a tidal river with one inlet and outlet opening at IJsselmonde (Rotterdam). Around 1500, there were already calls to replace the IJssel dam with sluices, as the Hollandse IJssel was seriously silting up.
silting up. That plan was never implemented, but between 1643 and 1949 there was still a small lock in the dam. The pond or 'wiel' at the foot of the IJssel Dam testifies to a dike breach in 1496.
IJsseldam
The dam is located south-west of IJsselstein, and since its placement, the floodplains no longer flooded. Before its construction, the Hoge Dijk, the Lage Dijk (as a summer dyke), and the IJsseldijk with summer road (also as a summer dyke) did provide protection. The placement of the IJssel Dam made it possible for the city of IJsselstein to be founded on part of the western floodplain of the IJssel. Several parts of the IJssel floodplain were significantly higher.
The Klaphek
The name of the dam refers to the nearby farm "Het Klaphek" or the hamlet of the same name. The village consists of a single street and currently belongs to the municipality of IJsselstein. The dam connects to the Lage Dijk Zuid (south of IJsselstein).
What else is there to see?
From the dam, another ditch runs northwards for a distance of several hundred metres behind the houses and farms on Lage Dijk Zuid. This ditch then splits westward as the Enge IJssel, and eastward as the Kromme IJssel.
Walking tip
The Hollandse IJsselpad is a 37 km walking route from the river's origin at Het Klaphek in IJsselstein to Gouda Goverwelle. The route is divided into four stages and follows the towpath along the river as much as possible. The route can be walked in two directions.