The man who created the crocodile for the film was none other than Stan Winston. Winston was also the creator of the monsters in Aliens (1986) and Jurassic Park (1993).
The crocodile as CGI or animatronic has about 3 minutes and 43 seconds of screentime.
Sheriff Keough's "big gun" was a fake gun made specifically as a prop for this movie. They even gave it a fake name, calling it a "Light Weight Forward Area Air Device Unit" which itself is a pretty good parody of military jargon. It was not an M-203 grenade launcher, which fires 40mm grenades. The "grenades" shown with the gun were a good deal smaller than 40mm.
Hector jokes at one point, that the crocodile was flushed down the toilet by some "a*shole" in Hong Kong, a reference to the film Alligator (1980), in which the little girl Marissas father flushes Ramon down the toilet, and grows into a behemoth, also in that movie Ramon dies by getting blown to pieces, in this the second crocodile gets blown up by the Sheriff's lightweight forward air device unit.
Betty White's character is told that PETA (People for the Ethical Treatment of Animals) would be interested to learn of her alleged mistreatment of her cows. In reality, White is a major on-air spokeswoman for PETA.
Hectors surname Cyr is an anagram of the word "cry", a nod to the famous tale that crocs weep with false remorse while devouring their prey. Now research has shown that some reptiles really do shed tears during a meal, but most likely for biological rather than emotional reasons, as the fluid from their tear ducts functions to clean and lubricate the eye, and is most prominent and visible when crocodiles have been on dry land for a while. In the case of American crocodiles and saltwater crocodiles, the tears help rid of the excess salt that they take in with their food.
The largest crocodile in captivity was Lolong who measured 6.17m (20ft 3in) when he died from pneumonia in February 2013 in the Phillipines. The crocodile depicted in the movie is over twice as long
In addition to the crocodile itself, extensive CG water work was done as the crocodile dives in and out of the lake. One key scene involves a CG helicopter that the crocodile attacks as it sits on the surface of the water.
A typical flatbed truck in the United States is around 48-53' in length and 8'6" across meaning the crocodile on the flatbed at the end would be at least around 45' long.
In the hospital, someone can be heard paging Mr. Miner in the background. Lake Placid was directed by Steve Miner.
The "Light Weight Forward Area Air Device Unit" is a 37MM flare launcher attachment for many military rifles such as AR15, M16, M4, AK47,OR COBRAY M11/9. Customized for the movie with its own stock that the Sheriff assembles it onto before he uses it. It is not a grenade launcher, just a flare launcher made to attach to a rifle.
Oliver Platt's character is named Hector Cyr. There is a Cyr Plantation in Aroostook County, Maine, where this movie takes place.