Data Provenance
Why Now Stats + Caveats
Why Now — Source-backed Stats with Caveats
2.0.0
2026-02-23
U.S. aquifer depletion has accelerated to 25 km³/year — 3x the 20th-century average rate of ~9.2 km³/year.
measured
USGS SIR 2013-5079 (Konikow 2013), updated with GRACE-FO satellite data
Rate is a national aggregate; depletion is spatially uneven. Some subregions are stable while others face rapid decline.
Colorado River flows since 2000 have been roughly 20% lower than the 20th-century average, with 16.5 MAF allocated against 12-13 MAF actual flow.
measured
U.S. Bureau of Reclamation + peer-reviewed attribution studies
Exact percentage varies by baseline window and method. Lake Mead is at ~1,065 ft (Jan 2026), down ~150 ft from 2000.
Leading climate scientists project >60% probability of unprecedented megadrought in the American Southwest this century.
measured + modeled
Cook et al. 2015 (Science Advances): >80% under RCP 8.5. Williams et al. 2022 (Nature Climate Change): 2000-2021 was worst 22-year drought in 1,200 years, 42% attributable to anthropogenic warming.
Probability is scenario-dependent and regional (SW US). Under lower-emission scenarios, probability decreases. We use >60% as a conservative cross-scenario aggregate.
Federal water infrastructure investment is 4-5x lower than transportation, with an annual gap of $80-100 billion.
measured
ASCE Infrastructure Report Card (drinking water: C-) + federal budget analysis
IIJA allocated $55B for water (largest-ever federal investment), but the annual gap persists. State and local spending supplements federal, but total remains below need.
ASR portfolio economics show BCR 2-4:1 under drought and 7-17:1 under megadrought, but are marginal (BCR 0.83) under normal hydrology.
modeled
Document 09 engineering cost model, 10 MAF/yr reference portfolio, 2026 USD
This is fundamentally an insurance investment. Economics only become strongly positive under drought — which is exactly when the infrastructure is needed. Honest presentation of the normal-case BCR <1 is essential for credibility.
Raw file: /research/why-now-stats.json