Coordinates: 29.357747, 30.860934
The Bahr Yussef (“the waterway of Joseph”) is a canal which connects the Nile River with Fayyum in Egypt.
In ancient times, it was known as Mer-Wer (the Great Canal). The Arabic name refers to the Hz. Yusuf عليه اسلام
It is believed by some people that this canal was built on the orders of Hz. Yusuf عليه اسلام
In prehistoric times, the canal was a natural offshoot of the Nile which created a lake to the west during high floods.
The canal was built into the natural incline of the valley, creating a channel 15 km long and 5 m deep that sloped into the Fayyum depression.
As the surrounding area changed at about 230 BC, the Bahr Yussef eventually became neglected, leaving most of Lake Moeris to dry up creating the depression that exists today and the modern province of Al Fayyum.
The Bahr Yussef still exists today, feeding water northwards into the Birket Qarun, parallel with the Nile.
One Story (Highty speculative and doubtful)
Some time after the famine, that pharaoh the Hz. Yusuf عليه اسلام served under had died.
Then when the new pharaoh took over, and brought in new advisors (many of which may not have even been alive during the plenty/famine times), a jealousy arose amongst those advisors over Joseph because of the great things that he had done.
So they urged pharaoh to challenge Hz. Yusuf عليه اسلام to do it again by turning a dry, barren area into a fertile land.
So Hz. Yusuf عليه اسلام engineered a canal the fed off of the Nile and created a large lake region, which irrigated the large region into a very fertile land area. That canal is called the Bahr Yusef (or Canal of Hz. Yusuf عليه اسلام), and still stands today.