Pumping water using a small electric pump, does it need to be potable?

Question

I am doing a little DIY project where I need to pump 4-5 gallons of water that is less than 100'. I need the pump to be able to run dry as it starts to pull the water, then it would pump the water.

Does this need to be a potable pump? Non-potable pumps are much cheaper and I will only be running the pump like twice a month for 20 minutes at a time.

Potable example: http://www.attwoodmarine.com/store/product/Potable-Water-Pump

non-potable example, a little pond pump from Home Depot.

With it being hard plastic, I just can't see how it could have an issue. The water does need to be drinkable..

Answer 1

If you will be drinking the water, you need a potable water pump. "Potable" means "safe to drink." No matter what, if needs to be able to start dry, you need a "self-priming" pump.

Answer 2

If the water needs to be potable, use materials (pumps, tubing, hoses, etc.) rated as potable. The problem is often leaching. Many materials, including metals and plastics that seem impervious, can leach dangerous materials (lead, other heavy metals, various plastic based chemicals), many of which have been shown to be health hazards, and more that are being found on a regular basis. See, e.g. this article

It sometimes seems like overkill, but why take the chance. If you amortize the cost over the years the pump (or other items in the drinking system) will be in use, safety may be pretty cheap.