Flume rides became the must have ride for amusement parks and theme parks during the 1960's and 1970's with each park adding these popular rides to offer thrills and a way to cool off from the summer heat. Larger parks (and especially theme parks) often had not just one but two flume rides in order to add capacity and bigger and bigger thrills.  In many cases parks would have a log flume and add a second Hydro Flume model, which offered more exciting and wetter thrills.
	Following the 1974 opening season of Great Adventure, the park looked to expand and improve for 1975, adding many new attractions. Without a doubt, one of the most popular attractions of the inaugural season was the "world's longest" Log Flume, with huge lines of guests waiting to ride and cool off from the summer heat. For the 1975 season, a second, even taller flume was added with the construction of the Hydro Flume. The new ride was built on the opposite side of the park from the existing Log Flume to help spread out the crowds in the park. The ride was placed in the wooded area in the middle of the Great Train Ride. The entrance and the exit for the Hydro Flume required the installation of a railroad crossing so guests could procede into the heavily wooded queue area that wound into the station set far off the main pathways of the park.
	Opening Date: Late July 1975 Manufacturer: Arrow Development Co. Model: Hydro Flume Lift Height: 85 feet Track Length: 1598 feet Speed: 40 mph Number of Boats: 36 Number of Guests per Boat: 4 - 5 guests Hourly Capacity: 2000 guests per hour Gallons of Water: 350,000 Gallons Features: Twin Chutes Spillway Drops Hydro Jumps Rotary Station Ride Cost: $2.2 million
	The Hydro Flume had several major differences from the Log Flume, though often guests would barely notice them. First (and most distinctive) was the style of the boats. Unlike the rustic logs of the Log Flume, the Hydro Flume featured sleek space age style boats which may have lead to the ride being renamed "The Moon Flume" for the 1976 season.
	1975--Hydro Flume/Hydra Flume 1976-1978--Moon Flume 1979-1980--Ride the Rapids 1981--Splash Down 1982-1989--Kodak’s Splash Down 1990--Splash Down 1991-1998--Irrawaddy Riptide 1999--Riptide 2000-2005--Poland Springs Plunge 2006--Riptide
	Unlike the Log Flume, the Hydro Flume featured only one large lift hill and one large drop, with half the ride up high above the tree tops, and the other half traveling through concrete troughs at ground level. To help increase capacity, the large, steep drop was actually two chutes with gates at the top and bottom to send boats down alternating sides. This also helped reduce the flow of water from the trough so the boats would roll down the drop rather than float down, allowing safer operations. Gates at the top could also hold boats to space them out properly for safety. When the boats plunged down the drop, they sped to the bottom where they would encounter a "hydro jump" which sent them into a moment of air time before plunging into the deeper trough of water with a large splash. The height, speed and splash were all higher, faster and wetter than what the Log Flume provided, giving guests more of what they loved.
	The Hydro Flume in many ways was more of a roller coaster than a flume. Boats went up the lift hill where they were dropped into the trough of moving water. The water was pumped up from the main reservoir below the lift hill, then flowed down the trough which gradually sloped along its course to the chutes. Boats floated along the trough powered by gravity and carried by the current. When the course reached the chutes, the water was spread out between the two, making it fall in a thin sheet. This allowed the boats to roll on their wheels, riding on steel plates on the surface of the fiberglass. Wheels on the sides of the boats kept them straight as they plunged down. The lower portion of the flume was a concrete trough at ground level, in some areas surrounded by concrete ponds designed to catch the water the boats would splash and drain it into the main reservoir. Just like the Log Flume, initially most of the ride was out of view of the guests, travelling through the heavily wooded area. From below riders on the train could glimpse the flume's layout, and the upper trough was visible from the Big Wheel and SkyRide. With the addition of Lightnin' Loops in 1978, the Hydro Flume became more visible both from the loading platforms for the coaster and from the ground as more trees were removed. In 1981 with the addition of Roaring Rapids next to the Flume and behind Lightnin' Loops, more of the ride was visible to guests.
	The Great Train Ride was removed from Great Adventure, improving access to the flume as well as opening more land for development. For the 1979 and 1980 seasons the Hydro Flume was known as "Ride the Rapids", but that name would change with the addition of Roaring Rapids for the 1981 season.  For most of the 1980's the Hydro Flume was known as "Splash Down", with long lines of guests making their way through the wooded queue to cool off.  Guests loved the park's water rides and even with the addition of Roaring Rapids in 1981 and Splashwater Falls in 1987, the flumes continued to draw crowds.
	Just like Great Adventure's Log Flume, the Hydro Flume was designed to maximize throughput. The rotary loading platform (or turntable) afforded quick and easy loading of boats as they continued to move through the station, allowing the ride's crew to group guests to fill boats completely. This provided for a throughput of up to 2,000 guests per hour, which was more than almost any attraction in the park.
	For the 1988 season, Great Adventure made many changes and updates to attractions in the park to try and help enhance safety. One of those changes made was the permanent closure of the outer chute of the Hydro Flume, eliminating the gate that would direct the boats to alternating sides and reducing the capacity of the ride slightly. This eliminated the problems of boats periodically jamming at the top of the drop. Along with the closure of the second chute, the "Hydro Jump" at the bottom of the drop was removed, taking away the pop of air time as the ride hit the water at the bottom. This eliminated some of the ride's excitement and one of the features that differentiated it from the Log Flume.
	For the 1991 season,  Six Flags Great Adventure looked to add waterpark type elements to the theme park, and introduced the new Adventure Rivers area which was built in the area around and beneath the Hydro Flume. As part of the new themed area the Hydro Flume got a new look and new identity as it was incorporated with the new theme.
	The Adventure Rivers area was themed to the world's great rivers, with areas and attractions representing North America, Asia, Africa and Australia. The flume was included in the Asian themed section, taking on the name Irrawaddy Riptide. The Irrawaddy River in Myanmar is one of the world's greatest rivers carrying the water from the Himalayas to the Indian Ocean. The area in the middle of the flume became home to the largest and most visible tower of the new area, the Asian Tower which featured four long, twisted yellow tubes and filled much of the area that had just been the wooded infield. New bridges were built to allow guest to cross the concrete trough of the flume to access the slide complex.
	The flume was cosmetically changed to make it fit the new theme, getting a bright red canvas roof for the station to replace the old blue and white one. The canvas featured round gold designs, and bright new banners and signage were added to the queue to give the flume a new look and feel. The addition of the other water rides of Adventure Rivers around the flume meant more guest traffic than ever, as well as making the ride more visible with so many trees having been removed.
	The new attractions added as part of Adventure Rivers were fun, but suffered from low throughput, and many guests were disappointed that they were required to be fully clothed to ride them in the rubber rafts instead of being real waterslides like those found in waterparks. The flume and Congo Rapids rides which had been included in the Adventure Rivers area continued to be popular attractions over time, while the slides quickly became passé. As the 1990's came to a close, so did the time for Adventure Rivers. Other theme parks were adding full waterparks either as separately gated aquatic parks or as add-on's to their theme park.   Six Flags management made plans to do the same at Great Adventure and wanted to expand the theme park with more rides and attractions to try and grow attendance.
	For the 1999 season the slides of Adventure Rivers were removed to make room for Great Adventure's second children's area, Looney Tunes Seaport which filled the area under the flume. The flume bisected part of the new section, so a new bridge was built across the area at the bottom of the drop. This allowed non riders to watch their friends splash down as well as offering a new access point that was fully accessible for strollers and wheelchairs. The staircases installed for Adventure Rivers were impractical for guests looking to get into the children's area.
	With the addition of the Looney Tunes Seaport, the flume's trough was realigned to make more room for the new rides being installed. The flume's station was repainted in blue and yellow and the ride took on the shortened name "Riptide" now. While the Asian Slides had been removed, the footings for the supports that had been installed in the reservoir remained.   In 2000, Six Flags Hurricane Harbor opened as part of the Great Adventure complex, and with the addition of a full waterpark and the additional strain of staffing it along with the 25 new rides added in 1999 meant that the flume would operate on a more limited basis. It now only operated in the peak summer season and even then only on the busiest days when staff was available.
	While Riptide was relegated to a more limited role in the park, it was saved for many seasons through sponsorship. Poland Spring water sponsored the ride from 2000 through 2005, when it took on the name Poland Spring Plunge. Additionally another source of revenue was added with coin operated sprayers being placed on the bridge, giving guests a chance to spend their quarters on soaking their friends (or strangers) as they passed underneath.
	After thirty years of operation, the flume was starting to show its age.  The ride was requiring more maintenance each season, with large sections of the trough requiring repair or replacement. In 2005 the side of the drop that was still open needed replacement, including major work taking place on the fiberglass, the concrete at the base, and the installation of new steel rails for the wheels. The rising maintenance costs along with the declining fortunes of Six Flags as a company at the time meant that rides nearing the end of their life or with declining popularity were often on the chopping block.
	The Poland Springs sponsorship of the flume ended in 2005, so for the 2006 season it went back to the Riptide name.  Once again a great deal of time and money was spent on maintaining the ride though it only operated for a few months during peak season. The new management of Six Flags was looking to cut expenses, and with the limited operations, spiraling costs and redundancy of the Hydro Flume, along with plans for a new themed section, a decision was made to remove the ride after thirty one years of delighting guests.
	The flume was removed in the 2006-2007 off season to make way for the new Wiggles World area of the park which took over part of the Looney Tunes Seaport area as well as the flume's queue and ride area.
	While the flume was removed to create Wiggles World, the former station and platform became the new Wiggle's World stage. The canvas structure was painted in bright new colors to fit the new theme and rows of seats were installed in what had been the ride's queue area. Even years after the Hydro Flume's removal, evidence of the ride's existence can still be found today especially when viewing a show taking place on the elevated circular stage In Safari Kids which once was the Hydro Flume's station platform.