In western Nepal in 2022, our $35 turbidity logger hit 800 NTU within 20 minutes of the season’s first storm, and the elders called that first flush “marta pani” — killer water — because they won’t drink it until the third rain. Do you see similar names or rules where you work, and have your sensors shown the same early-season spike?
Here in Oaxaca we see the same: first storm is like shaking a dusty rug — our stream jumps to 700–900 NTU in about 15 minutes, folks call it ‘agua brava.’ We now hold the intake closed until rainfall tops 10 mm or turbidity dips under 200 NTU, and a cheap first-flush diverter dumps the first 8–10 minutes off roofs… Do you see the second rain still spiking if the dry spell before it was long?
$35 logger caught 820 NTU here; we bypass intake 30 minutes — ‘marta pani’ indeed… Do you trigger at 150 NTU?