Operation of river locks

Operation of river locks

River locks make rivers with great level differences safe for boating.



river lock, gate, lock chamber, lock system, transportation, water transportation, shipping, watercraft, river, water level, height difference, geography

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Boating on rivers with large differences in level is dangerous. To ensure safe boating, lock systems are constructed that equalize such level differences.

A lock system is basically a series of water chambers; it consists of lock chambers separated by sluice gates. The amount of water in the locks and thus their water level can be controlled.
When a gate is opened, water flows from the higher level towards the lower level until the levels are equalized. When this happens, the boat passes to the next lock. This is how it moves from lock to lock.

When a boat heading downstream arrives at the sluice system, the level of the headwater is higher than that of the first lock. Therefore, the water level in the lock has to be raised so that the boat can pass to that lock through the gate. When the top gate is closed, the water level is lowered to the level of the second lock.

Then the bottom gate is opened and the boat passes to the second lock. Finally, the water level of the last lock is lowered to the level of the tailwater.
This is where the last gate is opened and the boat leaves the lock system. The water level under the boat is lowered step by step.

When boating upstream, the water level is gradually raised.

Now you can see how a lock system works, how the water level in the locks is raised or lowered. A sluice gate actually has two components. So far you have only seen the top pair of gates, but now you can also watch what happens in the lock.

When the top gate opens, so does a lower gate. The lock system is like a flight of stairs. When the gates open, the stairs become flat; the principle is similar to an escalator.

The flattened stairs let the water flow towards the lower level. The water in the bottom swirls and rocks the boat; people on the boat therefore need to hold onto something while passing the lock, especially on small boats.

Now watch from the deck how a boat passes a lock. You are boating downstream and reach the top of a lock system. You must wait for the lights that indicate that the locks are ready.

Soon the gate opens and you can enter the first lock. If you look back, you can see the gates have already closed behind you. Now you can feel the water level dropping. It looks as if the walls were growing but it is actually you who is ‘sinking’ in the lock chamber, since the amount of water in it is being reduced.
Then the lights on the next gate indicate that the gate is open and you enter the next lock. This continues until you find yourself in the tailwater of the river.

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