Death from below: Investigation of inhibitory factors in bloom development during a wastewater effluent diversion

Abstract

Please cite this article as: Kudela, R.M., Lucas, A.J., Hayashi, K., Howard, M., McLaughlin, K., Death from below: Investigation of inhibitory factors in bloom development during a wastewater effluent diversion, Estuarine, Coastal and Shelf Science (2015), ABSTRACT Eutrophication of coastal waters is an urgent and globally increasing problem. A significant source of nutrients to Southern California coastal waters is direct discharge of secondarily treated wastewater effluent from regional Publicly Owned Treatment Works. The planned diversion of treated wastewater from the Orange County Sanitation District's main (5-mile) pipe to a shallow 1-mile pipe off Huntington Beach, CA in autumn 2012 provided an unprecedented opportunity to monitor the response of the coastal phytoplankton community to a major anthropogenic loading event. Despite the continuous release of approximately 11.07x10 6 m 3 of effluent containing 1743 µM ammonium, there was virtually no detectable change in phytoplankton biomass, in striking contrast to the harmful algal bloom dominated community that quickly developed in response to a comparable diversion in Santa Monica Bay in 2006. Field and laboratory studiesdemonstrate that disinfection byproducts associated with enhanced dechlorination were present in the discharged water, and that these compounds had a strong inhibitory impact on phytoplankton photophysiology and growth, lasting 24 h for photosynthetic performance and at least 3 d for growth, assessed as change in chlorophyll. Thus, the perhaps fortuitous unintended consequence of enhanced chlorination was the production of inhibitory compounds that suppressed the potential phytoplankton response over a large swath of the continental shelf during the diversion.

Unravelling the effects of treated wastewater discharges on the water quality in a coastal lagoon system (Ria Formosa, South Portugal): Relevance of hydrodynamic conditions

“…Increased inputs of organic matter driven by wastewater discharges may additionally promote the (respiratory) activity of heterotrophic prokaryotes, leading to oxygen depletion and, ultimately, eutrophication of the receiving water bodies (Lajaunie-Salla et al, 2017;Pérez-Ruzafa et al, 2019;Renzi et al, 2019). Wastewater discharges have been also reported to induce alterations in ecosystem food web structure and metabolism, for both exposed (Howard et al, 2017;Kudela et al, 2017) and confined coastal systems (Yuan et al, 2010;Leruste et al, 2016;De Wit et al, 2017;Pérez-Ruzafa et al, 2019;Renzi et al, 2019;Taylor et al, 2020). Furthermore, disposal of untreated and treated wastewaters can also promote the contamination of natural coastal systems with faecal material and associated pathogenic microbes (e.g., viruses, bacteria; Mozetič et al, 2008), that can negatively impact edible aquatic resources, namely at shellfish harvesting waters, human health, and socio-economic activities (Biancani et al, 2012;Pandey et al, 2014;Rodrigues and Cunha, 2017;Florini et al, 2020).…”

Variation in growth rate, carbon assimilation, and photosynthetic efficiency in response to nitrogen source and concentration in phytoplankton isolated from upper San Francisco Bay

“…, Kudela et al. ). The advantage of using F v /F m is that the response time is on the order of minutes to hours following the onset of the stress, resulting in significant time savings compared with waiting for a response in growth rates (Kromkamp et al.…”