Background: The injection of illicit drug and illicit drug related overdose deaths continues to rise across the United States. In many parts of the country safe injection facilities are being considered to address the epidemic and confront outdoor and public injection. To better understand injection drug users who injection in public or outdoor locations, we examined the demographic and behavior correlates associated with this practice. Hepatitis C virus (HCV) infection remains a significant public health problem in the United States, with people who inject drugs disproportionately afflicted. Over the last decade rates of heroin use have increased, with young persons (18-25 years) demonstrating the largest increase. Methods: We conducted a cross-sectional study in young people who currently injected illicit drugs (age 18-35 or ? 5 years of illicit drug injection) in the Lower East Side of New York City from 2005 to 2012 to examine the risk factors associated with public and outdoor injection drug use as well as antibodies to HCV among young adults who began injecting during the era of syringe services programs. Results: Among the 714 participants enrolled, 53.9% of participants injected predominately in public and outdoor spaces and the prevalence of antibodies to HCV was 48.0%. The majority of participants identified as homeless (68.8%), white (74.5%), and male (68.3%). Characteristics independently associated with public and outdoor injection included homelessness, methamphetamine use, recent incarceration, and less hygienic injection practices. Risk factors independently associated with HCV seropositivity included older age, more years injection, higher injection frequency, injecting crack/cocaine, history of overdosed, lacking confidence in being able to avoid HCV infection, using more used syringes, and injecting primarily in public/outdoors spaces. Conclusion: Our findings indicate a substantial percentage of young injection drug users in the Lower East Side of New York City are injecting predominately in outdoor and public locations. These findings suggest that currently debated harm reduction interventions such as safe injection facilitates may be able to impact the negative consequences of injection illicit drug use. Despite access to needle exchange program in New York City, the seroprevalence of hepatitis C in young and recent injectors remains high. Risk factors associated with more active substance use (more years injecting) are a strongly associated with HCV infection. Additionally this is the first study to demonstrate an association between public and outdoor injection and hepatitis C infection. In light of the growing acceptance of supervised injection facilities in many cities around the world, studying the potential impact of these facilities on public and outdoor injection and HCV transmission could provide added evidence to support their implementation.