Water quality improvement project for initial rainwater pollution and its performance evaluation.

Area of Science:

• Environmental Engineering
• Water Quality Management
• Urban Hydrology

Background:

• Urban water pollution is a significant environmental challenge, with initial rainwater runoff being a major contributor.
• Effective performance evaluation of initial rainwater pollution control projects is crucial but rarely documented.
• Understanding pollution levels under various rainfall scenarios is essential for targeted mitigation.

Purpose of the Study:

• To describe engineering measures for improving initial rainwater quality in Anhui Province, China.
• To evaluate the performance of an initial rainwater interception project using key water quality indicators.
• To assess the effectiveness of these measures in mitigating urban water pollution.

Main Methods:

• Selection of three key water quality indicators: ammonia nitrogen (NH3-N), chemical oxygen demand (COD), and total phosphorus (TP).
• Analysis of pollution severity under light, moderate, and heavy rainfall conditions.
• Application of a single-factor evaluation method to assess water quality enhancement benefits.

Main Results:

• Initial rainwater pollution severity increases with rainfall intensity (light < moderate < heavy).
• Lotus Pond showed 100% compliance for NH3-N and TP, and 74.91% for COD with tertiary drinking water standards.
• Fushan Road Drainage experienced significant reductions: 91.43% for NH3-N, 10.49% for COD, and 57.33% for TP.

Conclusions:

• The implemented engineering measures successfully controlled nitrogen and phosphorus pollution from initial rainwater.
• Chemical oxygen demand remains a challenge, necessitating specialized treatment strategies.
• The water quality improvement project offers a valuable technical reference for urban water ecological management.