We are water. Literally. So we need to be drinking a fair amount of it daily. Try to drink tap water in reusable bottles. Unless there is something very wrong with your municipal water or you know your well water is contaminated, there is no reason to drink bottled water. Bottled water is a farce. It usually is the very municipal water you think you're avoiding by buying tap. So you're spending several dollars on something that is free – and less regulated than municipal water, I might add. A total rip off. And then there are all of the eco-implications and repercussions of the actual bottles. Think of the energy used to make those bottles, fill them with water, and then transport them all around. Sure, most places recycle the plastic most water bottles come in (PET #1) but many of those bottles wind up in the trash or in the gutter, not in the recycling bin. And they take 1,000 years to break down in a landfill. Spending money on something that is free and then drinking out of virgin plastic for maybe an hour that will then sit in a landfill for 1,000 years doesn't sound like good common conscious. So we don't do it.
Everything else is a pretty huge category. Think about what you drink over the course of a day. Green the items you drink the most of to make the biggest impact. For me that's coffee, some tea, and wine. I don't drink much hard alcohol or beer but there are certain local/organic or just organic versions of both. Choose these. It's amazing to me how many people who eat a very conscious diet but forget somehow to drink sustainable coffee, tea, and wine. These, like your veggies, are plants. They can be highly sprayed or unsprayed. There are considerable labor issues when it comes to both – always look for Fair Trade coffee and tea. Depending on where you live, these can be local or from very far away. When it comes to coffee, shade-grown is another label to look for. The choices for organic/biodynamic/natural/sustainably grown grapes abound. Organic wine used to have a bad reputation but these taste great. Depending on where in the country you live, American wine might be less green than French. It has to do with transportation miles and economies of scale, not to mention irrigation.
What I don't delve into in the book is the sort of drinks that line the beverage aisle and drinks cases in most supermarkets. Soda isn't a conscious choice. If you want bubbles with flavor, buy a home seltzer maker, use it, and add some home squeezed juice. If you choose to drink it, do so knowing how much water is involved and how the sugar that is processed into high fructose corn syrup affects both you, the farmers that raise it, and the earth. Juice is an odd middle ground territory. If you don't live near an organic orange grove but do live near a low spray apple orchard, drinking the latter for breakfast can have considerable conscious impact. Besides, so much that is sold in bright plastic bottles as juice is mainly water and sugar, with flavor and maybe some juice mixed in. A good way to drink real juice is to buy a juicer and make it yourself.