During her travels for Hajj, she witnessed the water shortage that the Hujjaj suffered from in the dry desert. She had spent over 2 million dinars on improving the water supply of Makkah and the surrounding province. This included the construction of an aqueduct from the spring of Hunayn, 95 kilometres to the east, as well as the famed “Spring of Zubaida” on the plains of Arafat. The canal is a remarkable feat of engineering and construction at such a time when no modern technology was available and thus, it was named after her – Nahr-e-Zubaida (The Zubaida Canal).

The canal was built on a path that pilgrims walked through between Makkah and Taif. She called prominent engineers and surveyors from different parts of the world to build this canal. After surveying the entire area, they decided to bring the canal from the Hunayn valley where a water spring from the mountains provided water to the residents for irrigation. The area was rocky, the land was barren and dry, and the weather very hot. It was very difficult to sustain a canal on the surface of the earth, so the engineers planned to make a subterranean canal in the form of a tunnel (aqueduct), with water stations raised above the ground at different intervals, where from people could meet their water needs.

At the orders of Zubaida, the entire area of Hunayn valley, which contained a spring and other sources of water was bought. To bring the water through the mountains was nothing less than a Herculean task, which required a large number of workers, enormous funds and expertise for cutting the mountains and digging the barren and rocky hills. After several years, the canal was brought down to Jabal-e-Rahmah (the Mountain of Blessings) in Arafat, and then to Mina and Muzdalifa.

Earthquake

In 245 AH, an earthquake in Makkah caused several cuts and cracks to the canal but they were immediately repaired at the request of the sitting Khalifa. Later, several rulers made additional improvements to the canal.
With the passage of time, the canal seriously suffered from a lack of repair and maintenance, and consequently, the supply of water stopped. In addition, over the span of several centuries, new sources of water had been made available to meet the water needs and therefore no attention was given to restore the canal.

Recent renovations

In 1295 AH, a committee was formed by the Saudi Government to look after the repair and maintenance of the canal. The committee was able to regulate its water. However, unfortunately in 1344 AH, a huge flood in the Numan valley damaged the canal and its water supply stopped for three months. King Abdul Aziz, who took over in 1343 AH, had it repaired but at the beginning of 1400 AH, the water of the canal stopped completely due to certain reasons and could not be restored.

In recent times, the rulers of Saudi Arabia took special interest to meet the water needs of the pilgrims. This, however, did not leave the great canal forgotten. The Crown Prince of Saudi Arabia, Abdullah, in 2001, gave the instruction to revive the canal to substantiate the water supply to Mecca and save the remarkable heritage of the Muslim Queen.

At any cost

“Do it even if it costs a dinar for every axe stroke”

These were Zubaida’s words when her treasurer explained that it would cost a fortune to build a water canal.

On the bank of River Dejlah (now called River Tigris), a crowd had gathered outside the beautiful palace of the queen, awaiting her audience. The queen appeared on the balcony and very gracefully addressed the crowd: "Today I close all the account books on the canal. Those who owe me money need not pay back. And those whom I owe, will be paid immediately and double the amount." Saying this, she ordered that the account books be thrown into the river and said: "My reward is with Allah."

The project cost approximately 5.950 kilograms of gold, which came from Zubaida’s own fortune and jewellery.

King Abdul Aziz had also created a charitable trust under Zubaida’s name.