I use the liquid laundry detergent bottles to store powder detergent, TSP and anything powdery which would be damaged in a flood.
I store washing or flushing water in plastic containers. Drinking water is stored in glass bottles only. My canning jars are filled with either food or water.
I have a trick for storing TSP so it doesn’t harden into a block. I pour a container of TSP powder into a jug and then fill it with water. You have a concentrated solution of TSP with non-dissolved crystals on the bottom. Use the liquid and refill with water, re-stir and use till no crystals are left. Repeat.