The Marina Trash Skimmer is a product designed to clean waterways by skimming trash from the surface, as well as circulating and aerating water via a pump. An absorbent bilge pad can also be installed to absorb oil. The Marina Trash Skimmer can typically clean about 300 gallons of water a minute for 24 hours a day, or the equivalent of about 20 swimming pools of water. The most commonly collected items by these devices include styrofoam, glass bottles, cans and containers, plastic bags and wrappers, cardboard, free-floating organic material, fishing products, cigarettes, and oil (if an oil pad is included). The unit is 6’ wide x 4’ deep x 18” freeboard which gives it a 24 square foot area where all of the trash can be retained until it can be emptied.
The Marina Trash Skimmer is a technology that has been used in other cities. The Port of San Diego tested units at four San Diego Bay marinas outfitted with absorbent bilge pads and evaluated their effectiveness over an eight-month period. Each unit was regularly maintained by the marina staff to remove accumulated debris and replace the bilge pad, as needed. Based on their experience, the frequency of maintenance required was dependent on the rate of debris accumulation in each area.
According to their report, the Port was unable to evaluate the impact of the unit on chemical water quality due to an issue with their sampling program, but they did determine that the skimmers were successful in reducing debris at each of the four sites. The report did not specify the frequency of cleaning, the number of staff required for maintenance, or other operational details. However, the report did specify that the units are powered by electricity and use about 25 Kwh/day which translates to $2 per day in energy costs at commercial prices. One Marina Trash Skimmer costs approximately $12,000 with a warranty provided on the molded parts (ten years), water pump (two years), and control panel (three years).
In June 2016, the City reached out to representatives of Seabin, a company that developed an automated trash bin to collect floating litter, oil and detergents from surface waters, regarding a potential pilot program to reduce litter debris from the waterways. The product, which was in development at the time, is similar to the Marina Trash Skimmer with a smaller cleaning capacity of approximately nine pounds of litter (under five gallons). Following several conversations, Seabin and the City did not reach an agreement and therefore a pilot program was not launched.
The proposed pilot program consisted of installing a Seabin at the south end of Lake Pancoast or at the marine slip in South Pointe Park to reduce high volumes of trash that accumulate at these two locations. For Lake Pancoast, The One Hotel and Aloft own the adjacent seawalls and submerged lands in the area and the City proposed reaching out to see if they would be willing to install this product on their property and provide the regular daily maintenance. For the location at South Pointe Park, existing Parks and Recreation Department staff was recommended to assist with daily maintenance. For both instances, the pilot program was proposed with an educational campaign focused on reducing litter.
Clean waterways are critical for our local ecosystem, economy, and quality of life. To that end, the City utilizes a waterway maintenance contractor to remove floating litter and submerged debris three times per week from our 63 miles of waterways. In 2017, the waterway contractor removed nearly 114,000 pounds of trash.