Increased imports and consolidation of smaller warehouses into larger facilities may be drivers behind the recent trend in companies requiring more trailer parking at their mega-distribution centers.   By 2020, the AIWA (Atlantic Intercoastal Waterway Association) predicts U.S. highways, railways, and ports will move 70% more freight than they did in 1998. This increased cargo volume will create challenges for every player in the supply chain.       Freight flows by truck, which are nearing capacity today, will increase sharply in the future, causing more trucks to be on the highways. Trailers have gotten larger, space is being consumed by trailers waiting in queue to be unloaded, and truck courts are being used as storage buffers. These factors drive the need for more trailer parking and staging areas…a trend which shows no sign of letting up.   Distribution center consolidation also adds to this problem. Many companies are reducing the number of DCs to drive efficiency and reduce costs, but this necessitates more land to accommodate the larger number of trucks these buildings must handle. In markets like Atlanta, Dallas, Chicago, San Francisco and Los Angeles, it is common for distribution centers to have one million square feet or more under roof.   The Perris Distribution Center (Perris, CA), developed by Los Angeles-based IDS Real Estate Group, is considered to be the nation’s largest single spec building. The DC, which has an area of almost 1.7 million square feet, has parking for 842 trailers.   Whether companies begin sharing lots, constructing additional parking facilities, or leasing space from adjacent DCs within industrial parks, there is no question that more land area is a major criterion to accommodate the trailer parking needs of these vast centers.