Pioneer Museum in El Centro.
This regional museum shows the history of the Imperial Valley. It is entirely based upon voluntary labour and money. And you'll need 3 hours minimum to see it. The main theme is the irrigation of this valley.
In 1904/05 the Colorado flooded the entire valley, because most of the area is under sea level. Because of a massive build-up of sediments down in Mexico the Colorado flood waters built up the Salton Sea. It took 3-4 years to stop the flooding. Engineers build a wooden railroad bridge across the flooded area. Then they let trains, loaded with boulders and rocks, run across day and night. They tipped their load down besides the bridge and that way a dam was built to separate the flooded area laying below sea level from the active part of the river. Slowly dry land showed up on the upper side of the dam.
The damage caused by the flooding was extensive. Farmland was washed away, houses destroyed. Deep flood channels were washed out. But the people of the Imperial Valley started the reconstruction of their farms and dwellings and turned it into what is today known as the fertile Valley where major parts of the U.S. produce is grown.
Agriculture and Irrigation in the Imperial Valley