A bad storm washes away Chompy the Beaver's dam, so he starts chomping on all the wood at Farmer Yumi's farm! Ryder and the PAW Patrol have to fix the chomped barn and fence, but that's just the beginning. Chompy has been chowing down all over town! Chase has to track the busy beaver, while the rest of the pups help rebuild Chompy's home.
As the episode begins, Adventure Bay is enduring another nasty thunderstorm. At Farmer Yumi's pond, a beaver escapes his dam just in time as the fierce winds cause the dam to collapse and be completely destroyed. As the beaver wonders about how to rebuild it, he gets an idea and sets off.
A short while later, at Yumi's farm, the beaver slips out through a hole near the back of the barn with a piece of newly chewed wood it acquired for rebuilding its dam. Inside, Chase is helping Yumi collect hay bales for her chicken coop, along with Zuma. As they enjoy watching Yumi's chickens lay their eggs to be collected underneath, the coop suddenly creaks and groans, then collapses, sending eggs flying, and causing the chickens to fly clear and start scampering around the barn in a panic. Chase is able to subdue them with some baskets, but as Yumi investigates the damage to the coop, a louder groaning causes both her and the pups to watch as the entire front wall of the barn falls over! Investigating the damage, Yumi realizes it has to be Chompy the Beaver who's the cause of all this. With the rest of her barn structurally compromised by Chompy's damage, Yumi knows she needs the PAW Patrol, and Chase and Zuma head off to get Ryder.
Ryder is busy tickling Rocky when Chase and Zuma arrives to tell him about the trouble at Farmer Yumi's. Ryder summons the pups, and as Marshall reaches the Lookout, he kicks a soccer ball he was bringing with him into the Lookout, but it ricochets off the elevator doors and knocks him into Skye and Rubble before rolling back into the elevator itself. Marshall jokes that he scored again, earning laughs from the others, and they head up. Once topside, Ryder passes out the orders: Rocky and Rubble will aid in the repairs to Yumi's barn and chicken coop, while Chase will track down Chompy and figure out why he chewed on everything at Yumi's. The team deploys, and it is not long before Chase sets off to find Chompy, while Rubble and Rocky set to work with the temporary repairs to the barn and chicken coop, using spare planks of wood for the barn wall, and old chair legs to support the chicken coop, much to the chickens' appreciation.
Chase soon finds Chompy, but forgets that trying to capture Chompy in his net won't work, as Chompy chews through the ropes around his face to remind Chase about that. Following Chompy instead, Chase has Ryder join him at the pond to discover that the beaver dam has been destroyed by the storm and Chompy was just trying to rebuild it. Contacting Rubble and Rocky, Ryder has them bring as much spare wood from the farm to the pond as they can to help rebuild the dam.
No sooner has Ryder finished that call, when he gets one from Mayor Goodway, revealing that the totem pole she just finished carving has been sabotaged by a beaver as well. Realizing that another beaver must be on the loose if Chompy is still at the pond, Ryder dispatches Chase to find the beaver quickly.
In town, the beaver Ryder sent Chase after is now chewing away at the large trunk of the tree that Alex's tree fort is in. Alex calls Ryder to let him know, and Ryder redirects Chase to Alex's tree fort. When Chase arrives, there is not one, but two beavers chewing away at the trunk. As the tree shifts slightly as the trunk is weakened further by the beavers' chewing, back at the pond, Ryder notices Chompy smack his tail in the water and remembers that beavers communicate with their tails. Chase attempts to try it with his tail, and it works! The beavers climb aboard Chase's patrol truck, and he brings them back to the pond, just as Rocky and Rubble arrive with the spare wood.
In a short while, the dam is rebuilt, and Chompy and his brethren are very grateful. They slap their tails as a way of saying "thank you". When it is revealed that the new dam comes with a water slide, Ryder allows the pups to join the beavers in some water slide fun. When Rubble and Chase ask Rocky to join them, he decides to just enjoy getting some sun. Chompy and the other beavers put a quick end to that when they chew away the end of the plank Rocky is on the opposite end of, causing his weight to tip the plank, and him, into the water. As Rocky is thoroughly upset over getting wet, Chompy, his brethren, and the rest of the team, share a good laugh over it to end the episode.