What's next for Trump's border wall: Designs start now, construction planned for June

The push to seal the U.S.-Mexico border moved ahead as federal authorities published two official requests for contractors to propose prototype segments of a border wall.

Construction of the segments will proceed quickly, with plans to begin within three months, putting the work on the wall prototypes solidly in the middle of the hot summer months in the Southwest.

The prototypes are a precursor to the border wall that was a signature campaign promise of President Trump, though the full-length wall itself is expected to be built through a separate bidding process later.

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The specifics of the prototype project and the bidding process are detailed in two, nearly identical 132-page Requests for Proposals, posted Friday night to the Federal Business Opportunities website.

What kind of wall?

Each prototype will be 30 feet long and built in San Diego, according to the requests for proposals.

Beyond that, bidding contractors have much latitude in what kind of wall they propose.

Under the new timeline established in the documents, interested bidders will have two weeks to create and submit a design concept of what the border-wall prototype will look like, with two design options for companies.

One will be exclusively for "reinforced solid concrete" prototypes, while the second for "other" materials is more vague and does not specify the type of materials that can be used in the design.

Other requirements include:

• A "physically imposing" height of no less than 18 feet but preferably 30 feet tall.

• Anti-climbing mechanisms, either by ladder or other tools like hooks that humans may be able to get across.

• Prevent tunneling 6 feet below ground.

• For breaches to the wall (using building or cutting tools, or torches) to take at least one hour in concrete designs, and 30 minutes in the "other" designs.

• Accommodate surface draining, a particularly sensitive issue in the uneven, Arizona desert that can easily flood with heavy rains.

• Be able to accommodate "pedestrian and automated mechanized vehicle sliding gates."