Streamflow answers for the decisions that
can't wait on fieldwork.

Most watersheds aren't well-monitored. Most deadlines don't allow for a multi-year data collection effort. Lynker Spatial Hydrology delivers validated streamflow simulations at any location, across any time period, so your team can move forward with confidence, not caveats.

Built by expert hydrologists and Earth system scientists with applied experience in operational forecasting, watershed modeling, and large-sample hydrology across consulting, academic research, and federal agency support contexts.

Validated against 22 years of observations
22 years of validation across thousands of catchments WYs 2001–2022
NSE 0.87 spring freshet skill, Connecticut River headwaters example USGS 01138000 · WY 2020

NSE = Nash-Sutcliffe Efficiency. A score of 1.0 is perfect; below 0 means the model is worse than using the average. See the case study below for full context.

The Problem

Most water decisions are made without enough streamflow data.

Rivers and streams are dynamic. They change across landscapes and through time, with responses from individual storm events to long-term hydroclimatic trends. To assess these systems accurately, you need simulations that capture that variability, not static approximations.

Streamflow gages cover a fraction of the river network. Permit decisions, flood assessments, and water supply analyses routinely rely on regional approximations, outdated baselines, or the National Water Model. None of these were designed for site-specific accuracy or ungaged watersheds.

Lynker Spatial Hydrology closes that gap. We apply large-sample hydrology methods to run validated simulations directly on the Lynker Spatial Hydrofabric, a connected representation of every catchment, flowpath, and junction across the US, to characterize streamflow at any location, even where no gage exists. Our models have been validated against decades of observations across thousands of catchments, including data-sparse regions where the uncertainty matters most.

Lynker Spatial Hydrofabric, Colorado Front Range, Rocky Mountains to High Plains
Lynker Spatial Hydrofabric, Colorado Front Range, Rocky Mountains to High Plains. 11,717 catchments · 11,560 flowpaths. Every node is a potential simulation point.
Under the Hood

How the model works, and what the results look like.

Simulations run directly on the Lynker Spatial Hydrofabric, which means water moves through a physically connected network, not a statistical approximation. Catchment response propagates downstream the way it does in the real world, from headwaters to major river corridors.

We pick the right model for your watershed, not the other way around.

Different watersheds behave differently. Snowmelt-dominated basins in the Rockies don't respond like rain-fed catchments in the Southeast. Our model-agnostic framework spans data-driven and physics-informed approaches, including NOAA's Next Generation Water Resources Modeling Framework, and lets us match the method to the landscape rather than forcing every problem into a single model structure. The result is more accurate simulations, better-characterized uncertainty, and outputs calibrated to what your project actually needs.

What this looks like in practice: USGS 01138000, Connecticut River headwaters, Water Year 2020. We simulated daily streamflow across the full contributing catchment network through the spring freshet and compared our output against the observed gage record. The right panel shows prediction skill for this basin compared to the NOAA National Water Model on the same period, one example of the kind of improvement we see in snowmelt-dominated systems.

Lynker Spatial Hydrology streamflow simulation, USGS 01138000, Water Year 2020
Catchment mean flow (mm day⁻¹) alongside simulated vs. observed gage discharge, USGS 01138000 · Water Year 2020. Simulated (orange) tracks closely with observed (white) through the full spring freshet.
Streamflow prediction skill comparison, Lynker Spatial vs. NOAA NWM
Spring freshet prediction skill, Lynker Spatial vs. NOAA NWM · USGS 01138000 · Water Years 2001–2022. Observed vs. simulated daily discharge across the spring freshet window (Mar 1–May 31). This is a single-basin example, not a large-sample benchmark.
NSE 0.87 Lynker Spatial
NSE 0.13 NOAA NWM
KGE 0.84 Lynker Spatial
KGE 0.58 NOAA NWM

Spring freshet · Mar 1–May 31 · USGS 01138000 · Water Years 2001–2022. Single-basin example. Higher is better for both metrics; 1.0 is perfect.

Who Uses This

The kinds of projects we support.

Across federal agencies, state programs, environmental consulting firms, and research institutions.

Hydrologic baseline development and retrospective simulation across US states and territories
Surface water connectivity and flow permanence assessment
Watershed-scale hydrologic and ecological analysis
Flood and drought characterization
Multi-model hydrologic comparison and uncertainty evaluation
Hydrologic assessment across monitored and unmonitored watersheds
Operational Product

Need ongoing streamflow intelligence, not just a project deliverable?

The modeling described on this page can be operationalized through the infrastructure behind FlowFabric, Lynker Spatial's streamflow intelligence product. Where an assessment delivers a retrospective analysis for a specific project, FlowFabric provides the delivery layer: continuous, multi-model streamflow outputs as a data service, ready for dashboards, forecasting workflows, and decision systems that need hydrologic intelligence on an ongoing basis.

Assessment engagement
  • Project-scoped, defined deliverable
  • Retrospective or scenario-based
  • PDF report, geodata, or both
  • Ideal for permitting & planning
FlowFabric product
  • Continuous operational data service
  • Real-time & historical via API
  • Multi-model ensemble outputs
  • Ideal for dashboards & workflows
Get Started

Tell us what you're trying to answer.

Most engagements start with a scoping call. You describe the watershed, the decision, and the timeline. We'll tell you what's feasible, what the outputs would look like, and what it would take. No proposal overhead required.