The Colorado River delta has hardly seen any Colorado water in the past 30 years. The only water the river delta sees nowadays is seawater. The tidal movement of the sea leaves a fascinating pattern of veins in the mudflats..The 1.5 million acre feet of water that the USA delivers across the border into Mexico is completely used by cities like Tijuana and Mexicali. The majority, though goes into the irrigation of the vast agricultural area that covers the northern part of the delta. The line of agricultural fields slowly moves northwards though due to an increasing salinity of the area.