U.S. border colonias, otherwise known as Disadvantaged Unincorporated Communities, are rural settlements along the U.S. Mexico border with substandard housing conditions. Colonia residents often face inadequate access to necessities such as appropriate shelter, septic and sewer systems, and potable water. Water insecurity in colonias poses a particularly difficult challenge for residents who require clean water not only for consumption, but also household use in sanitation and hygienic practices. As of 2015, an estimated 30% of over five million US colonia residents lack access to clean drinking water, resulting in health complications and unsanitary living conditions. Preliminary health data collected indicates that due to water insecurity, colonia residents are more likely to contract gastrointestinal disease, be exposed to carcinogenic compounds from contaminated water, and experience psychosocial distress. Yet more comprehensive research needs to be conducted to understand the full breadth of the public health issue. A scoping review on water insecurity in colonias has not been completed before and could be beneficial in informing policymakers and other stakeholders on the severity of the situation while advising possible solutions.