When travelling to the Dominican Republic, it is not safe to drink tap water. Tourists are advised to stick to purified bottled water, which is widely available throughout the country. Hotels and restaurants use purified water for cleaning and cooking, and for making ice for their ice machines. People with sensitive stomachs should also use bottled water for brushing their teeth.
The microbes in the Dominican Republic's water can be difficult for some people to digest, as they are not used to the different ecological environment. To stay safe from intestinal bugs while enjoying your holiday in Punta Cana, it is best to stick to bottled water. Punta Cana is a safe place to visit, with extra police present in tourist areas. The local water quality and pollution is rated on a scale from 0% (lowest) to 100% (highest).
To avoid iced drinks during your stay, try the local concoction made by combining rum, red wine and honey, then steeping the mixture with tree bark and herbs. It is also recommended to get vaccinated for hepatitis A before travelling, as this liver disease can be transmitted through contaminated food or water. Although I didn't spend the night outside the resort, I did explore Santo Domingo and the coastal town of El Cortecito in the Punta Cana region.