Depending on the severity of a given sargassum infestation, the amount of sargassum that arrives on public beaches in the High Impact Zone (HIZ) during Sargassum Season usually runs between 5 to 10 cubic meters per day. And, in 2023, hiring an outside service provider to handle manual removal and proper* disposal of sargassum cost approximately MX $500/cubic meter.
Most property owners in the HIZ cannot afford the full cost of hiring an outside service provider to keep the federal zone sargassum free using manual removal alone. And expense is not the only problem with relying on manual removal alone. Manual removal of huge amounts of rotting sargassum also:
* causes beach erosion because so much sand gets removed with the sargassum
* does nothing to prevent the arsenic in sargassum from leaching into the sand and water
* does nothing to prevent hydrogen sulfide gases from corroding copper & silver in appliances
* is harmful to the health of the workers who remove it....AND...
* when improperly disposed of causes degradation of ground water and mangroves
NOTE: It is important to remember, however, that the GOAL of the barrier project is to reduce the amount of beached sargassum by at least 70% so that HIZ property owners can affordably manage manual beach cleaning of the sargassum that will still arrive on our public beaches. In fact, the HMB Sargassum Project has published these Best Practices in Manual Beach Cleaning for HIZ property owners.
The stench of rotting sargassum can be mitigated by spraying it with products that neutralize the smell. This product is environmentally safe and allows sargassum to dry out in place so that it can be more easily disposed of once weight and volume have been reduced. And, again, the HMB Sargassum Project does expect to use spray prior to removal of the sargassum that we project will still end up on the beach even after the barrier is installed. (If the barrier deflects 70% of incoming sargassum 30% will end up in the bay or on the beach):
Spraying alone, however, is not an effective way to mitigate sargassum infestations because it cannot prevent rotting unless the sargassum quantity is reduced enough to dry out. It does not stop sargassum from rotting, prevent metal corrosion, protect the reef, prevent beach erosion or mitigate other environmental impacts. Nor does it improve the beach going experience. And, in 2022 at least, supplies were somewhat limited.
Beach removal is the most common solution to a sargassum infestation but raking and dumping is generally not effective:
Beach removal causes erosion because it removes sand
Beach removal is a Sisyphean task: once the beach is clean, the next tide of seaweed is never far behind.
Beach removal fails to protect the reef or to ensure clean water for swimming and snorkeling.
Beach removal does not prevent unpleasant beach experiences for visitors who must put up with the stench, impediments to walking on the sand and unpleasant swimming experiences.
Beach removal is expensive. The average building on Half Moon Bay spends $$$/week on shoveling and disposal.
Careless dumping of decomposing sargassum seaweed can cause:
Direct and indirect damage to mangroves
toxic fumes from hydrogen sulfide cause flu-like symptoms in people
damage to expensive equipment
(such as air conditioning units, plumbing, and electric systems)
As you can see, the benefits of a barrier are significantly greater than Manual Beach Removal: