2021 – Oxygenation Demonstration Project Plans:
Summary: OPC will shift Demonstration Project to focus on a more promising new technology called Side Stream Saturation.
During the past two years, the primary focus of the Sarah’s Pond Oxygenation Demonstration Project was assessing the performance of nanobubble equipment. During these two years, despite the equipment being designed to deliver excess oxygen to the test basin, the oxygen levels failed to substantially increase, nor was it successful in eliminating or substantially decreasing hazardous algal blooms (HAB’s), (for a more background information on our research effort please the see the report written by our technical consultant D. Ken Wagner/ Water Resource Services Titled: Review of nanobubble experience at Sarah’s Pond, Orleans, MA – link below). The primary conclusion from this work is that the transfer efficacy from the nanobubble system was lower than expected. And whilst further improvements in nanobubble design will undoubtedly make it a promising future technology, our conclusion from our research is that it is not ready for ponds such as Sarah’s today. That said, there have been developments with an alternate oxygenation technology called Side Stream Saturation (SSS) that have lowered the capital cost of such systems, making it a very attractive approach for Sarah’s Pond. Testing of the system by SOLitude personnel in another location has provided promising results and the report of first successful use was published back in 2014 (Water Research, Vol 67, Dec 2014, pp 129-143).
With these developments, OPC has negotiated an agreement with SOLitude Lake Management to install new SSS equipment technology and monitor its performance in Sarah’s Pond over the next three years. Our goal remains unchanged: Provide sufficient oxygen to the test basin so that hazardous algal blooms (HAB’s) can be reduced or eliminated. For the demonstration research plan, we have chosen a 1hr power motor. The maximum dissolved oxygen capacity for this equipment is 18.1kg/D. This is well above our calculated target for success of 8-12kg O2/D.
How does SSS work:
SOLitude Lake Management has partnered with Vertex Aquatic Solutions for this research. The new patented Vertex oxygen system is equipped with a water pump specified for either freshwater or saltwater, an oxygen chamber, and plumbing to bring water from the target basin and return the water, oxygenated. The system has been designed to deliver the full capacity of oxygen, allowing Vertex to guarantee 100% oxygen transfer efficiency (OTE). The high oxygen water will be injected into the basin of Sarah’s Pond where it will be dispersed throughout the entire density layer. Injected oxygen behaves like coloring dye in a pool where it moves throughout the density layer shortly after injection. There are no bubbles made and no mixing to disturb bottom sediments or compromise thermal structure. This system allows the oxygen concentration in water and at the sediment interface to be far greater than what traditional aeration could provide, making, what Vertex Aquatic Solutions asserts, the best oxygenation system on the market.
A simplified schematic of the installation plan is below:
The installed unit will pump approximately 60 gallons per minute and consume only about 1.5kwh power.
Installation and monitoring began in April 2021.