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Beyond Ordinary

Grand Solmar at Rancho San Lucas in Cabo San Lucas, Mexico

By Juan Padilla

Water Flow

Because of the size, shape and varying depths of the lagoon, water flow and circulation were very strategically planned. To ensure proper circulation, the pool builder designed 87 floor returns fed with seven 6-inch lines, nine 6-inch anti-entrapment engineered floor suction lines, two 8-inch floor suction lines, eight 6-inch return lines for the water features, and six 6-inch skimmer lines. The flowrate was estimated at 4,872 gpm, and the total water feature flowrate was 2,400 gpm. The circulation system was designed to provide for a fast turnover rate when required, such as moments after a storm or high winds. Under normal circumstances, the equipment functions at an optimal flowrate to keep the water quality in check. "We also designed our own special skimmer returns," said Alvarez. In conjunction with the landscape architect's directions, the custom skimmers were made of masonry to blend in with the lagoon's esthetic design.

Equipment Room

The equipment for the lagoon is comprised of eight Pentair THS sand filters, seven Pentair EQ pumps each of which is 10 HP in size, three variable frequency drives (VFDs) and two BioShield UV units. Both the filters and pumps require some special maintenance routines due to the nature of the ocean's salt water in the lagoon as well as the sand and silt that flows regularly into the lagoon's waters.

Basically, the lagoon's environment requires a lot of backwashing. "One of the reasons we really like using the THS horizontal sand filters is that they have a hatch that allows us to visually inspect the sand directly, to see how dirty it is getting," explained Alvarez. "Sometimes the sand looks like chocolate!" As a result, maintaining the sand sometimes requires that the maintenance team manually clean the sand in the filters. The sand in the lagoon's filters is backwashed weekly and manually cleaned about every two months—though most of the debris tends to accumulate at the top of the filter.

The EQ pumps have very few parts that corrode because even the motor on these pumps is totally enclosed and fan cooled (TEFC). However there is quite a bit of plumbing both for the lagoon as well as for the many water features that are a part of in the lagoon—both waterfalls and water bubblers. Initially, the plumbing was experiencing an extreme "hammer effect" and so MAXA worked with Pentair and determined that three VFDs could give the pumps the soft start needed to stop the hammer effect. Prior to adding the drives, the plumbing was experiencing some violent shaking and the pressure was such that it caused the plumbing connection to fail. However the VFDs allow the pump to 'soft start' allowing the system to be pressurized little by little. And conversely, it also allows the system to soft stop as well, decreasing the pressure and eliminating the hammer effect. In addition, the soft start and stop help protect the pump motor reducing the amount of maintenance and replacement of parts. This is particularly important in an area that is fairly isolated from major distribution centers, potentially making replacement parts scarce. There has been a learning curve associated with the VFDs in this operation, as standard protocol in Mexico has always been to change the pump motor bearings annually, as a part of a regular maintenance program. With the VFDs it's important that maintenance personnel understand they no longer need open the pump motor. That in fact, it will reduce the life of the motor to do so. As the new TEFC motors on the Pentair EQ pumps in combination with the Acu Drive XS variable frequency drive, allow maintenance personnel to do virtually nothing in terms of maintenance on the pumps and is why Pentair is able to offer a longer warranty on these pumps.

In addition to the protection to the pumps and the removing of the hammer effect on the plumbing, the variable frequency drives have also provided added energy savings to the property owners. By being able to dial the pumps to the exact flow rate required, the pumps are able to use less energy.

The variable speed drives and the UV units are fairly self-sufficient. The UV units require very little maintenance outside of making sure the lamp is clean and functioning. The VFDs require minimal maintenance and, in this salty environment, just need to be checked for corrosion and cleaned or repaired as needed.

Becoming 'Lagoon' Experts

The lagoon at Grand Solmar has now been operating for two years. MAXA Watershapes took care of every detail in house until every kink was worked out of the system. Last year MAXA Watershapes turned everything over to the resort's maintenance department and supervised as needed. The results are so successful and the owners of the resort have been so pleased with the results that they are now building an extension or 'Lagoon Part 2' within the resort.

"We have now become 'experts' on ocean saltwater pools," explained Alvarez. "Because we do all the building and engineering, we are able to control the outcome and ensure success."

MAXA Watershapes has been building in the Cabo San Lucas areas for the past 20 years and is known for putting a lot of heart into its projects. "Because we do everything in house, we are knowledgeable about the process in ways that other construction companies aren't able to offer. Our customers trust us because we pride ourselves on being educated by attending seminars and training in the U.S., following all APSP codes, putting an emphasis on detail and therefore we are able to guarantee superior results," Alvarez said.

Now MAXA Watershapes can add "salt-water lagoon experts" to their list of qualifications.

Juan Padilla is a commercial and automation specialist for Pentair in LATAM (Latin American) & the Caribbean. He has been with the company since 2012, starting his career as territory service manager for LATAM. With more than 16 years in the industry. Padilla has held several positions including everything from service tech and installation manager to account manager. For more information, visit www.pentair.com.