A hydrologist figures out where water is, how much there is, how it moves, and how clean it is, then helps people make decisions about floods, droughts, supply and pollution. Most US jobs ask for a bachelor's degree in hydrology, geoscience, environmental science or civil engineering, and a master's helps for many consulting and agency roles. This roadmap builds from water-cycle basics and math, to field measurement, GIS and HEC-HMS/HEC-RAS modeling, to groundwater flow and contaminant transport, with a project at each stage. Everything here is free. You can do this one step at a time: each sk
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Every stage from beginner to expert, with lessons, practice drills, projects, interview questions and free resources. Free with a Rolearch account.
Stage 1 of 3 · about 12 weeks
Understand the water cycle quantitatively and be comfortable with the math, data and mapping tools every hydrologist uses.
Hydrologic cycle and water budgets
Every hydrology problem is a bookkeeping problem: inputs minus outputs equals change in storage (P - ET - Q = dS). If you can write and balance a water budget, you can reason about floods, droughts and aquifers.
Math and statistics for water data
Streamflow is messy and skewed. You need algebra, basic calculus, unit conversion and statistics (mean, percentiles, regression, probability) to describe it and to talk about a 100-year flood properly.
Excel and basic Python for data
Job postings list Excel constantly, and Python is now the standard for cleaning long time series. Automating the boring work lets you spend time thinking about the water.
GIS basics and watershed delineation
Water follows terrain. GIS lets you draw a watershed from a digital elevation model, measure its area and slope, and overlay land cover and soils, which are the inputs to nearly every model.
Reading real hydrologic data sources
Employers expect you to find and judge data fast. Knowing what a USGS gage record, a NOAA Atlas 14 rainfall depth or an NRCS soil survey really tells you separates a student from a working hydrologist.
Then 2 more stages (about 48 weeks in all) with lessons, drills, projects, 6 interview questions with strong answers and free resources.