Catchy & Short:
* Drop by Drop, Make it Stop.
* Water: Use it Wisely.
* Every Drop Counts.
* Save Water, Save Life.
* Turn it Off, Turn it On.
* Don't Let it Run Dry.
Action-Oriented:
* Fix Leaks, Save Water.
* Water Your Lawn, Don't Drown It.
* Water Conservation: It's a Drop in the Bucket.
* Shower Smarter, Save Water.
* Choose Water-Wise Appliances.
* Be Water Smart, Save the Planet.
Humorous & Engaging:
* Don't Be a Drip, Save Water.
* Water: It's Not Just for Drinking Anymore.
* Water Conservation: It's a Splashing Good Idea.
* Let's Get Wet with Water Conservation.
* Save Water, or We'll All Be Dried Up.
Educational:
* Water Is Precious, Treat It With Care.
* Water Conservation: A Lifelong Responsibility.
* Together We Can Conserve Water for Generations to Come.
* Water is Life: Save It, Respect It.
* Make Every Drop Count: Conserve Water for a Sustainable Future.
You can also make your own slogan by combining different approaches:
* Be Water Wise, Save the World.
* Turn Off the Tap, Make a Big Impact.
Remember to choose slogans that are relevant to your target audience and that effectively communicate the importance of water conservation.