Veteran Ald. Richard Mell laid out the basics of redrawing the lines of Chicago’s 50 wards on Wednesday, saying this go-around will be the most challenging in recent memory.

Two of the biggest challenges involve race: The city’s African-American population dropped by more than 181,000, while the city’s Latino population grew by about 25,000 according to last year’s federal census.

Black aldermen would prefer not to lose City Council seats while Latino aldermen are looking to pick up a few seats as the new ward boundaries are drawn.

“I ask you to keep an open mind if you possibly can, to understand that even though your ward may be statistically almost right, the ward next to you could be statistically way off, which will affect everybody. So nobody's ward is going to remain exactly the same,” Mell, 33rd, told colleagues.

Mell expects the process – in which ward boundaries are redrawn to reflect population changes so that each ward has roughly the same population – to begin in earnest around Aug. 1.

Ald. Ricardo Munoz said the Latino growth points to a need for four to six new Latino majority wards. “Just look at the math, in terms of who grew, who didn't grow, and how these populations are concentrated in different parts of the neighborhoods,” said Munoz, 22nd.

Asked how many new Latino-majority wards the council might see, Mell refused to speculate, but noted “the Asians may want one” — a reflection of the city’s growing Asian population.

Mell said he hopes the new ward map will have fewer of the strangely shaped gerrymandered wards that aldermen often design.

“We're going to try, hopefully, to keep them more compact and coherent, but we never know. It's going to be interesting,” Mell said. “It's going to be challenging, probably as challenging as it's ever been, and I've been through the 80s, 90s, 10s, and now this one.”

Mayor Rahm Emanuel’s administration has not given aldermen marching orders on the re-map process, Mell said. Aldermen will proceed with trying to work out a compromise map, and will keep Emanuel apprised, he said.

The last time the council redrew the map, the wards had to have populations of just over 57,000 people, Mell said. This time the ward populations will go down to around 53,000 each because of the city's population loss, he said.

The council has until Dec. 1 to approve a map, under state statute. But if any group of 10 or more aldermen endorse an alternative, the competing maps go to voters in a referendum next March, as they did two decades ago. That map still ended up being contested in court in a legal battle that lasted six years and cost $11 million.