bajío

The Bajío (lowlands) is a region of Central Mexico that includes the plains south of the Sierra de Guanajuato, in the state of Guanajuato, as well as parts of the states of Querétaro (the Valley of Querétaro) and Michoacán (particularly the surroundings of Zamora). In general parlance, it is usually associated with the States of Guanajuato and Querétaro, although it only forms a part of them. It is characterized by its highly technified agriculture, with annual precipitation on the order of 700 mm on average (one of the highest in the country). During the Viceroyalty, the area was known as the breadbasket of the country.
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n. shallows, area in a body of water where the water is not deep

= shallows.
Ex: In this way the fowler could work his way through the shallows to within gunshot of the fowl, so as to let fly with his rifle as they took off from the water.