Hop aboard for an unforgettable underground journey as Lost River Cave transforms into a glowing emerald wonderland! Glide through the cave’s mysterious passages, now shimmering green thanks to eco-friendly dye, and soak in the magic of this St. Patrick’s Day celebration. Every tour is packed with fun facts, natural beauty, and a little touch of Irish luck!

*Come rain or shine, the “paddy” must go on! However, high river levels could limit cave access and change the river’s emerald hue.

Ever wondered how rivers flow underground? Our friends at Crawford Hydrology Laboratory are bringing science to life with eco-friendly dye tracing! This special dye turns the river a brilliant green while helping scientists study water flow—completely safe for people, wildlife, and the environment. It’s science and magic all in one!

Who is CHL?

Crawford Hydrology Lab (CHL) is an environmental consulting group and research center at Western Kentucky University. Founded in the late 1970s by Dr. Nicholas Crawford, a pioneer of dye tracing, the lab played a key role in restoring Lost River Cave in the 1990s and developing its iconic cave tour.

What is dye tracing?

Dye tracing is a method of investigating the movement of groundwater. Dye trace investigations can be designed to solve environmental issues involving the origin, destination, routing, and velocity of groundwater flow.

What dye was used today?

Green 8 Dye used in small amounts to sustain water coloration for about 48 hours, is commonly found in everyday products like soaps and medications. There’s a good chance you’ve encountered this dye in your daily life!

Is the dye harmful to organisms living in the water?

The Green 8 Dye, used in small, controlled amounts, poses no harm to human health and is carefully selected for detection at minimal concentrations. In flowing streams, the dye is diluted quickly, ensuring only short-term exposure. Studies show no evidence that short-term exposure to Green 8 Dye harms aquatic wildlife.

In addition to our green-tinted boat tours, we’re offering a special educational program, Go with the Flow, for just $5, where you can dive deeper into the science behind this magical event. This program is perfect for ages 8 and up, and it’s a great way to learn while having fun. Be sure to reserve your spot fast—these programs fill up quickly!

• 10:30 AM & 3:30 PM: Open to the Public
  Join us as scientists from WKU’s Crawford Hydrology Lab share the fascinating science of dye tracing and its importance in our complex underground landscape. After the live dye injection demonstration, our Lost River Cave team will lead a fun, interactive educational game that’s perfect for curious minds.
• 1:30 PM: Member-Only Program
  This exclusive program is reserved for our amazing members! Not a member yet? Join today to gain access to unique behind-the-scenes experiences like this. To sign up for the 1:30 PM session, email Kate.

Little adventurers, this one’s for you! Check in at the front desk inside the Gift Shop to grab your scavenger hunt, then follow the clues, uncover hidden treasures, and see if you can outsmart the sneaky leprechauns hiding around the Park. Free, fun, festive, and perfect for the whole family!

Your adventure doesn’t end at the cave! Flash your shiny gold coin at Reserva for 50% off your first drink. Whether it’s a craft cocktail or a refreshing brew, it’s the perfect way to celebrate St. Patrick’s Day!

📍 Reserva
2440 Nashville Road, Suite 103
Bowling Green, KY 42104