Willem I Lock is a monumental lock in Amsterdam-Noord.
Location
Willem I Lock is just across the IJ from railway Station Amsterdam Centraal. The lock is on the IJ-end of the Noordhollandsch Kanaal, the other end is near Den Helder, where the Wadden Sea and North Sea meet. The location of Willem I lock is explained by the desire to place the IJ-end of the canal as close as possible to the Port of Amsterdam. For this it was built on the headland Volewijck, sticking out into the IJ.
History
First plan for a lock near the IJ
In late 1818 an inland waterway connection was established between Nieuwediep and Amsterdam. The complete connection could only be used by barges and small vessels that could lower their masts. However, the northernmost section could also be used by ships which could pass the (later) navy lock at Nieuwediep.
That same year, King William I asked Inspector General Jan Blanken for proposals that would enable ships to reach Alkmaar, and to pass it. The king also asked how ships could reach Amsterdam from there. Jan Blanken made several recommendations. One of the works that he proposed was a lock between Purmerend and Buiksloot near the Tolhuis at the Achterdigting. This lock was not constructed.
Ordering and construction of Willem I Lock
In 1819 the final plans for the Noordhollandsch Kanaal were made. The year started with the municipality of Amsterdam demanding locks of 40 Amsterdam feet wide for the canal. An Amsterdam foot is 0.2831 m. 40 Amsterdam feet is 11.324 m. An 1819 drawing by Jan Blanked indeed shows such a narrow lock, with fan gates on the large lock chamber. This narrow lock was not constructed.
In June 1819 the 'First proposal for the immediate construction of the Great Amsterdam Canal' proposed the immediate tender of a double lock near Tolhuis at the IJ, in July 1819. On 29 July 1819 the construction of a double lock near the Tolhuis was tendered at the same time as an identical lock at Purmerend. Somewhat later, on 5 May 1820 the works to dig the actual canal, mainly by expanding the Buikslotervaart and Purmerender Vaart were tendered. At the same time the construction of the Buiksloot Flood Gate, at Buiksloterdijk, was tendered.
Already in 1820 the lock was known as Willemssluis, or Willem Lock, after the king. On 19 July 1821 the king visited the locks. It was the first time that water was let into the chamber of the big lock. Near the lock was a tent with models of the locks and other works of the canal. This was the official opening of the lock, but it was not entirely finished. On 4 September 1822 the maintenance of the lock was tendered for 6 years, and in November 1823 the inside of the lock gates still had to be finished. On 13 December 1824 the frigate HNLMS Bellona entered Willem I Lock to commence the first trip on the completed Noordhollandsch Kanaal.
Soon Willem I Lock got facilities like a small harbor on the other side of the Tolhuis.
The passage of Steam Frigate Wassenaar
In late April 1857 the new, and therefore not fully loaded, steam frigate HNLMS Wassenaar arrived before Willem I Lock. She did not fit the lock. Therefore, Buiksloot Flood Gate was closed, and water let in from the IJ, making the stretch of the canal from there level with the IJ. The amount of salt water that entered the polder this way was quite considerable. On 2 May 1857 Wassenaar was pulled through.
On 3 May Wassenaar then used Purmerend Lock without any problem, even though the two locks were the same size. The explanation that was given, was that at Willem I Lock the water level decreases while the ship went through, while at Purmerend it increases. Which would make that at Willem I Lock the bow and stern of Wassenaar would hit the top of the lock gates. On the other hand, the extremities 'naturally' caused less trouble with the rising water at Purmerend. A possible different explanation is that at Willem I Lock the gates were much higher. At the IJ side these were 2.80 m above AOD, and that was again 1.1 m above Waterland level, so the set of gates at the IJ-side would be 4 m high behind Wassenaar, when she reached Waterland level. The Purmerend gates did not have to keep out the sea, and the lock itself bridged a difference of only 52 cm in summer.