Description

River Self-Purification: Streeter-Phelps Method

Performs a self-purification calculation using the Streeter-Phelps model, which simulates the oxygen dynamics and BOD (Biochemical Oxygen Demand) in a river. This method calculates the degradation of organic matter and the oxygen replenishment through reaeration over a specific river length, helping in assessing water quality.

Input Parameters

Parameter	Default Units	Description
Flow	$m^3/s$	Water flow rate
Cross section area	$m^2$	Cross-sectional area of the river
River length	km	Length of the river
Upstream BOD	mg/L	Biochemical oxygen demand at upstream
Upstream dissolved oxygen	mg/L	Dissolved oxygen concentration upstream
Temperature	°C	Water temperature (default: 20°C)
Deoxygenation constant	$d^{-1}$	Rate of oxygen consumption
Reaeration constant	$d^{-1}$	Rate of oxygen replenishment

Output Parameters

Parameter	Default Units	Description
Flow	$m^3/s$	Output water flow rate
Downstream dissolved oxygen	mg/L	Oxygen concentration at the downstream point
Downstream BOD	mg/L	BOD at the downstream point
Critical dissolved oxygen concentration	mg/L	Minimum dissolved oxygen concentration
Critical length	km	River length where oxygen reaches a minimum
Concentrations table	-	Table of dissolved oxygen along the river