What immediate action must be taken if a deep pit latrine reaches capacity?

When a deep pit latrine reaches its capacity, the correct immediate action is to close the latrine. This is essential because continued use of a latrine that is at capacity can lead to sanitation hazards, including overflow or contamination of the surrounding area. Closing the latrine prevents further use and helps to ensure that health risks, such as the spread of disease, are minimized.

After the latrine is closed, proper measures should be taken to manage the waste, such as seeking alternatives like constructing a new latrine or emptying the existing one if feasible. However, the immediate priority is to prevent any further use that could exacerbate the situation.