Now here's an interesting news item. In Yuma, Arizona, they want to build a moat to protect the border. And it seems to have a lot of support. According to this Reuters article,

Most plans to gain control of the porous U.S.-Mexico border focus on some combination of fence. But this city in far west Arizona is looking to build a moat.Faced with high-levels of crime and illegal immigration, authorities in Yuma are reaching back to a technique as old as a medieval castle to dig out a "security channel" on a crime-ridden stretch of the border and fill it with water.

Yuma County Sheriff Ralph Ogden, who supports the proposed project, brings up the medieval moat connection:

The moats that I've seen circled the castle and allowed you to protect yourself, and that's kind of what we're looking at here.

The proposed moat would be in the Colorado riverbed:

The proposal seeks to restore a stretch of the West's greatest waterway, the Colorado River, which has been largely sucked dry by demand from farms and sprawling subdivisions springing up across the parched southwest and in neighboring California.

Here's an article about the Colorado River , here's a map of the Colorado watershed. In the Yuma area, by the way, the U.S. - Mexican river runs mostly north-south, not east-west. There could be an environmental advantage to the moat, as well:

The plan to revive the river, which drains from the Rocky Mountains through the Grand Canyon and runs for 23 miles (37 kilometres) along the border near Yuma, seeks to create a broad water barrier while also restoring a fragile wetland environment that once thrived in the area.

Sheriff Ogden says that

What you are building is a moat, but it's bringing the life and the wildlife back. It's innovative thinking. It doesn't take much brainpower to build a 12-foot high fence around something, but this is unique.

Here's the first stage:

The project is starting with a desolate 450-acre patch of scrub and thickets known as Hunter's Hole, a once-thriving wetland on the border a few miles southwest of Yuma that has become a haven for drug smugglers and illegal immigrants crossing from Mexico and a headache for local law enforcement.

Sheriff Ogden explains the current situation:

"It's in the United States, but it's become a no-man's-land, an area where bodies were dumped, where people and drugs were smuggled over the border," said Ogden, whose deputies share much of the responsibility for tackling border-related crime with federal police.

How would it be constructed ?

Engineers plan to dig a "security channel" up to 10-feet (3 metres) deep and 60 feet (18 metres) wide through the problem area, which lies a short way inside the border. The dirt removed would be used to create a levee along the outside to give U.S. Border Patrol agents an elevated patrol road overlooking the line.

It would provide advantages for the birds and the local residents:

The area would also be replanted with native sedges and rushes to provide habitat for threatened local species such as the Yuma Clapper Rail, a secretive marsh bird. Backers say it would also provide a space for residents of Yuma, a farming town popular with winter visitors, to walk and fish.

And the project's backers have an ambitious plan:

The organization behind the project would like to extend it the entire course of the Colorado River, which marks the U.S.-Mexico border, in what it sees as an environmental recovery program that complements the Border Patrol's task.

Environmentalists and the Border Patrol working together!

"It doesn't replace the Border Patrol's efforts, it supplements them. At the same time you are restoring habitat in a secure environment and creating a place to relax," said Charles Flynn, the executive director of the Yuma Crossing National Heritage Area Corporation.

Unlike some other border plans, the moat proposal has widespread approval:

The planned revival of the Colorado River, where it carves through desert peppered with fertile farmland, is something of a standout. It has won the backing of the federal Bureau of Land Management, which owns the land; the Bureau of Reclamation, which has provided a grant to drill wells and pump groundwater, and a letter of support from the Border Patrol. Also on board are Yuma City Council and local residents including the Cocopah Indian tribe, who have farmed the river's flood plains for centuries.

The project even has support on the Mexican side of the border !

Perhaps more surprisingly, it has also won support across the boundary in Mexico, where plans to build border fences are eyed with suspicion. Local environmentalists there have embraced the project and plan to work in tandem to restore the wetlands on the Mexican side."Instead of putting up walls and promoting division, we can promote security and friendship," said Osvel Hinojosa, the director of Pro-Natura, an environmental group in northwest Mexico, of the proposal."Moreover, instead of damaging the environment, we can improve it."

Sounds like a great plan, with wide support. So dig that border moat !