How NYC Health + Hospitals Delivers Patient Data in 5 Minutes with Snowflake

In a city of eight million, NYC Health + Hospitals carries an outsized burden: it is the safety net for those with nowhere else to go. With homelessness in New York City reaching levels not seen since the Great Depression, the health system needed to understand its most vulnerable patients not just as episodic cases but as whole people — with shelter histories, chronic conditions, and complex social circumstances. That required data infrastructure equal to the challenge.

Before modernizing on Snowflake, NYC Health + Hospitals managed healthcare data across fragmented systems. Payer data from MetroPlusHealth and other insurance subsidiaries arrived on five-day cycles, leaving care coordinators, managed care teams, and finance departments working from stale membership records. Protected health information from dozens of sources demanded careful governance, but legacy tools made security and auditability cumbersome rather than built-in.

The solution centered on building a unified data hub on Snowflake. The team rearchitected payer data ingestion to create automated pipelines that pull membership and claims data continuously. Snowflake Secure Data Sharing allowed external partners and city agencies to access and write to shared databases without moving data or duplicating it. Snowflake Horizon Catalog provided role-based access controls and audit trails that satisfied the compliance requirements of a public healthcare system handling sensitive mental health and clinical records.

The operational shift was profound. Membership data that once took five days to process now arrives in five minutes — a 1,440x improvement in delivery time. That speed means care coordinators can intervene with timely information when a patient appears in an emergency room after a shelter visit, connecting the dots that previously required days of administrative delay. Over 100 billion rows of healthcare data now reside in a single, governed environment, providing a holistic view of patient populations that was previously impossible.

Looking ahead, NYC Health + Hospitals is using Snowflake Cortex AI to experiment with generative AI across dozens of identified high-priority use cases. An enterprise AI advisory board is evaluating how to deploy AI responsibly in a system that serves populations already marginalized by societal bias — ensuring that the models amplifying care do not amplify inequity.