Bottled water is inefficient, expensive, and produces large amounts of plastic waste. Instead, use a refillable water bottle and tap water; if you like you could use a water filter to cleanse the tap water and chill the water in the fridge. Do yourself a favor and get a good reusable bottle and take it everywhere.
Plastic bags are appallingly wasteful to the environment. It is believed that 100 billion plastic shopping bags are used in America each year, and only 1-3% of worldwide plastic bags are recycled. This means a huge amount of waste, much of which ends up in our environment. When you go shopping take reusable bags and if you forget them ask for paper instead of plastic.