The Distribution of Road Salt in Private Drinking Water Wells in a Southeastern New York Suburban Township

Widespread changes in water temperatures, salinity, alkalinity and pH have been documented in inland waters in North America, which influence ion exchange, weathering rates, chemical solubility and contaminant toxicity. Increasing major ion concentrations from pollution, human-accelerated weathering and saltwater intrusion contribute to multiple ecological stressors such as changing ionic strength and pH and mobilization of chemical mixtures resulting in the freshwater salinization syndrome (FSS). Here, we explore novel combinations of elements, which are transported together as chemical mixtures containing salts, nutrients and metals as a consequence of FSS. First, we show that base cation concentrations have increased in regions primarily in North America and Europe over 100 years. Second, we show interactions between specific conductance, pH, nitrate and metals using data from greater than 20 streams located in different regions of the USA. Finally, salinization experiments and routine monitoring demonstrate mobilization of chemical mixtures of cations, metals and nutrients in 10 streams draining the Washington, DC–Baltimore, MD metropolitan regions. Freshwater salinization mobilizes diverse chemical mixtures influencing drinking water quality, infrastructure corrosion, freshwater CO 2 concentrations and biodiversity. Most regulations currently target individual contaminants, but FSS requires managing mobilization of multiple chemical mixtures and interacting ecological stressors as consequences of freshwater salinization. This article is part of the theme issue ‘Salt in freshwaters: causes, ecological consequences and future prospects’.

Section: (A) Freshwater Salinization Syndrome Mobilizes Mixtures Of Mmentioning

confidence: 99%

Section: (A) Freshwater Salinization Syndrome Mobilizes Mixtures Of Mmentioning

confidence: 99%

Novel ‘chemical cocktails' in inland waters are a consequence of the freshwater salinization syndrome

Kaushal

Likens

Pace

et al. 2018

“…B 374: 20180019 of North America, 25 to 50% of applied road salts enter groundwater, leading to groundwater chloride concentrations as high as 2800 mg l 21 [50,51]. For example, in southern New York (USA), more than 50% of wells used for drinking surpassed the United States (US) Environmental Protection Agency secondary drinking water recommendation of 250 mg Cl 2 l 21 [52]. Furthermore, fixing road-salt contaminated water supplies in two towns in New York (USA) cost $4.7 million (20 homes) and $13.2 million (500 homes), respectively [53].…”

Section: Consequences Of Salinizationmentioning

confidence: 99%

Regulations are needed to protect freshwater ecosystems from salinization

Schuler

Cañedo‐Argüelles

Hintz

et al. 2018

110

Anthropogenic activities such as mining, agriculture and industrial wastes have increased the rate of salinization of freshwater ecosystems around the world. Despite the known and probable consequences of freshwater salinization, few consequential regulatory standards and management procedures exist. Current regulations are generally inadequate because they are regionally inconsistent, lack legal consequences and have few ion-specific standards. The lack of ion-specific standards is problematic, because each anthropogenic source of freshwater salinization is associated with a distinct set of ions that can present unique social and economic costs. Additionally, the environmental and toxicological consequences of freshwater salinization are often dependent on the occurrence, concentration and ratios of specific ions. Therefore, to protect fresh waters from continued salinization, discrete, ion-specific management and regulatory strategies should be considered for each source of freshwater salinization, using data from standardized, ion-specific monitoring practices. To develop comprehensive monitoring, regulatory, and management guidelines, we recommend the use of co-adaptive, multi-stakeholder approaches that balance environmental, social, and economic costs and benefits associated with freshwater salinization. This article is part of the theme issue ‘Salt in freshwaters: causes, ecological consequences and future prospects’.

“…As salinization of freshwater ecosystems resulting from deicing and anti-icing salts continues, the regulatory and management challenge for winter road maintenance programmes will be to balance the need to protect public safety and reduce the economic costs of winter storms with the need to protect environmental health and infrastructure integrity related to excess salt, and to address potential drinking water/public health related to increased dietary intake of sodium [4,21,115,116]. Our study found low temperature can reduce the frequency or intensity of salt-related toxic events expected based on winter de-icing activities that increase NaCl concentrations.…”

Section: (C) Regulatory and Management Implications Of The Relationshmentioning

confidence: 99%

Temperature affects acute mayfly responses to elevated salinity: implications for toxicity of road de-icing salts

Jackson

Funk

2018

Salinity in freshwater ecosystems has increased significantly at numerous locations throughout the world, and this increase often reflects the use or production of salts from road de-icing, mining/oil and gas drilling activities, or agricultural production. When related to de-icing salts, highest salinity often occurs in winter when water temperature is often low relative to mean annual temperature at a site. Our study examined acute (96 h) responses to elevated salinity (NaCl) concentrations at five to seven temperature treatments (5–25°C) for four mayfly species (Baetidae: Neocloeon triangulifer , Procloeon fragile ; Heptageniidae: Maccaffertium modestum ; Leptophlebiidae: Leptophlebia cupida ) that are widely distributed across eastern North America. Based on acute LC50s at 20°C, P. fragile was most sensitive (LC50 = 767 mg l −1 , 1447 µS cm −1 ), followed by N. triangulifer (2755 mg l −1 , 5104 µS cm −1 ), M. modestum (2760 mg l −1 , 5118 µS cm −1 ) and L. cupida (4588 mg l −1 , 8485 µS cm −1 ). Acute LC50s decreased as temperature increased for all four species ( n = 5–7, R 2 = 0.65–0.88, p = 0.052–0.002). Thus, acute salt toxicity is strongly temperature dependent for the mayfly species we tested, which suggests that brief periods of elevated salinity during cold seasons or in colder locations may be ecologically less toxic than predicted by standard 20 or 25°C laboratory bioassays. This article is part of the theme issue ‘Salt in freshwaters: causes, ecological consequences and future prospects’.