CAIRO — An image of President Abdel Fattah el-Sisi of Egypt triumphantly piloting a ship full of smiling Egyptians appears Wednesday on the cover of the state-owned newspaper Al Akhbar al Youm to mark the successful excavation of what he has called a new Suez Canal. Really, it is a new channel, parallel to about a third of the existing canal, intended to reduce shipping bottlenecks.

Mr. Sisi, the former general who ousted Egypt’s first freely elected president two years ago, announced the plan last year and he vowed that the bigger channel would be completed in less than 12 months — a grand national project for the public to rally around. He declared it a cornerstone of his plan to revive the Egyptian economy.

The channel has been finished on schedule, but economists say it is unlikely to transform the water passage from the Mediterranean to the Red Sea. The added capacity will do little, they say, because the canal has not been operating at full capacity anyway, and global shipping remains in a slump.

Mr. Sisi will inaugurate the new canal at an elaborate ceremony on Thursday in Ismailia, about midway between the canal openings at Port Said in the north and Suez in the south. The Egyptian state news media is celebrating as if he had just won a military victory.

Television stations repeat slogans like “Egypt delights” and “Egypt’s gift to the world.” They are showing an army-produced music video that compares Egypt itself to a ship on the canal: “Pass with us,” the lyric says, “and life will be more beautiful.”

Religious authorities have instructed every imam to preach this Friday about the channel’s vast benefits to the Egyptian economy, recalling a historic battlefield victory of the Prophet Muhammad that involved digging a trench.

In Cairo, the government has strung electric lights along the banks of the Nile and on the rails of bridges. Giant Egyptian flags hang from the sides of skyscrapers. Banners celebrating the canal adorn roads in the capital and stores have announced special sales on Thursday.