# Services from hydrology-calc.x402tookit.com on Zero

> hydrology-calc.x402tookit.com serves 8 paid API services for AI agents, indexed by Zero. Each is callable per call with payment handled by Zero.

Canonical page: https://www.zero.xyz/host/hydrology-calc.x402tookit.com
Live health (JSON, refreshed every minute): https://www.zero.xyz/host/hydrology-calc.x402tookit.com/health.json

## Services

- [Manning Flow, Velocity & Hydraulic Radius Calculator](https://www.zero.xyz/c/manning-flow-velocity-hydraulic-radius-calculator-fbbaab04/llms.txt): $0.02/call via x402. Computes Manning open-channel flow rate, velocity, flow area, and hydraulic radius for rectangular, trapezoidal, triangular, or part-full circular channel cross-sections in SI or US customary units.
- [Hydrology & Open-Channel Calc – Froude Number](https://www.zero.xyz/c/hydrology-open-channel-calc-froude-number-153af0e5/llms.txt): $0.02/call via x402. Computes the Froude number (V / sqrt(g·A/T)) and classifies the flow regime (subcritical, critical, or supercritical) for rectangular, trapezoidal, triangular, or circular open-channel sections.
- [Hydrology & Open-Channel Calc – Critical Depth](https://www.zero.xyz/c/hydrology-open-channel-calc-critical-depth-7a795dd3/llms.txt): $0.02/call via x402. Computes the critical flow depth (Froude number = 1) for rectangular, trapezoidal, triangular, or circular open channels given a discharge rate.
- [Hydrology & Open-Channel Calc – Normal Depth](https://www.zero.xyz/c/hydrology-open-channel-calc-normal-depth-a3b1e376/llms.txt): $0.03/call via x402. Calculates normal (uniform-flow) depth for a given discharge in rectangular, trapezoidal, triangular, or circular channels using bisection method
- [Hydrology & Open-Channel Calc – Orifice Discharge](https://www.zero.xyz/c/hydrology-open-channel-calc-orifice-discharge-2e9c2291/llms.txt): $0.02/call via x402. Calculates orifice discharge flow rate Q = Cd × A × sqrt(2 × g × h) for round or custom-area openings, supporting multiple edge types and both SI and US units.
- [Hydrology & Open-Channel Calc – Rational Method Peak Runoff](https://www.zero.xyz/c/hydrology-open-channel-calc-rational-method-peak-runoff-029e5577/llms.txt): $0.02/call via x402. Calculates peak stormwater runoff flow Q = C × i × A using the rational method, supporting direct runoff coefficient, surface type lookup, or weighted sub-areas in SI or US units.
- [Hydrology & Open-Channel Calc – Time of Concentration](https://www.zero.xyz/c/hydrology-open-channel-calc-time-of-concentration-b2290029/llms.txt): $0.02/call via x402. Calculates time of concentration using the Kirpich formula and/or the NRCS lag equation for a watershed flow path, with method-specific applicability limits stated.
- [Hydrology & Open-Channel Calc — Weir Flow](https://www.zero.xyz/c/hydrology-open-channel-calc-weir-flow-93d87ee9/llms.txt): $0.02/call via x402. Calculates discharge (flow rate) over a sharp-crested rectangular (Francis), V-notch, or Cipolletti weir from head measurement, in SI or US customary units.

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