Why is Samba a salt water lake?

It isn't Samba. It's Great Salt Lake. The lake bed is in an area where there are mineral deposits, especially salt, in the area. There is no outlet, only inlets. Since the lake is relatively shallow, the surrounding areas dry out and salt and other minerals dry in the sun. read more

Salt Lake is the largest natural lake west of the Mississippi River. At the current level the Great Salt Lake is approximately 75 miles long and about 35 miles wide. Located in several wide flat basins, a slight rise in water lever expands the surface area of the lake considerably. read more

When there is no outflow of water, all the salts that were received into the water body gets accumulated and becomes more salty. Added to this, it's in semi-arid region of Rajasthan in which summer temperatures go very high. Unlike water, salts don't get evaporated and remains on surface itself. read more

Sambhar Salt Lake The Sambhar Salt Lake, India's largest inland salt lake, is located 96 km southwest of the city of Jaipur (Northwest India) and 64 km northeast of Ajmer along National Highway 8 in Rajasthan. it surrounds the historical Sambhar Lake Town. read more