I assume that this is a question about South Africa. If so, the Separate Amenities Act (more properly known as the Reservation of Separate Amenities Act) was passed in 1953. Thus, we can say that it started in that year.
The Separate Amenities Act was part of the South African system of apartheid. The point of this act was to ensure that whites and non-whites would be kept separate from one another in public accommodations. Segregation had existed to a great degree even before this act was passed. However, the official law of the land at that time was “separate but equal,” just as it was in the United States. Because courts sometimes upheld this standard, the Separate Amenities Act was passed.
The Separate Amenities Act did not just say that all public facilities could be segregated. It also explicitly stated that the facilities for white people could be better than those for non-whites. In other words, facilities could be separate and did not have to be equal. By passing this law in 1953, the South African government took another step in creating the apartheid regime that continued to exist until 1994.
The best answer to your question, then, is 1953.
The Reservation of Separate Amenities Act began in 1953. In South Africa, a white minority had control of the government and wanted to stay in power. The Reservation of Separate Amenities Act separated the blacks from the whites. Segregation was found in many places including restaurants, buses, hotels, theaters, and bathrooms. Usually, the facilities for the black people were worse than the facilities for the white people. This was part of the system of apartheid that existed in South Africa for many years.
Eventually, international pressure was put on South Africa to end the apartheid system. Some countries refused to trade with South Africa, allow travel to South Africa, or play their teams in various sports. This pressure helped to bring about change in South Africa. The Reservation of Separate Amenities Act ended in 1990. Apartheid ended in 1994.