Below Friant Dam (RM267), the San Joaquin flows west-southwest out into the San Joaquin Valley – the southern part of the Great Central Valley – passing north of Fresno. With most of its water diverted into aqueducts, the river frequently runs dry in a 150-mile section. This lack of riverwater begins in the between Friant Dam and Mendota, where it is only replenished by the Delta-Mendota Canal (RM 205) and the Fresno Slough, when the Kings River is flooding. From Mendota, the San Joaquin swings northwest, passing through many different channels, some natural and some man-made. Northeast of Dos Palos, it is only joined by the Fresno and Chowchilla Rivers when they reach flood stage. Fifty miles (80 km) downstream, the Merced River empties into an otherwise dry San Joaquin (RM118).