Livestock Effluents: Regulations and Valorization

Livestock effluents, primarily generated by agricultural and livestock activities, are a significant environmental concern due to their potential impact on water and soil quality. Proper regulations, management, and valorization of livestock effluents play a crucial role in preserving the environment and ensuring the sustainable development of agriculture.

The Sommet de l’Élevage focuses on the valorization of livestock effluents as well as the rules governing their management.

What Are Livestock Effluents?

Livestock effluents refer to the waste generated by livestock farming activities, in both solid and liquid forms. Solid effluents include manure, which results from the mixture of animal excrement with bedding materials such as straw, wood shavings, or similar substances. Manure is relatively dry, making it easy to handle and store, and it can be composted for reuse.

Liquid effluents include:

• Slurry: A liquid mixture of animal feces, urine, forage debris, and little to no bedding material.
• Slurry runoff: Liquid draining from manure, consisting mostly of urine and rainwater that falls on manure storage areas, creating a liquid known as leachate.
• Brown water: A mixture of animal excreta and rainwater that falls on uncovered areas frequented by animals.
• Green and white water: Wastewater from cleaning milking parlors and milking equipment.

Factors such as housing methods, animal type, diet, bedding levels, and other aspects influence the type and quantity of waste produced. In essence, livestock effluents encompass various types of waste generated by farm animals, and responsible management is essential to minimize their environmental impact.

Regulations on Livestock Effluent Management

Environmental regulations on livestock effluents impose strict standards for the responsible handling of waste generated by agricultural activities. These regulations, such as water laws and nitrate directives, apply to all types of farms, with varying requirements based on the size, type, and operation of the farm.

Compliance with these regulations is now essential to qualify for various subsidies, including those from the Plan de Compétitivité et d'Adaptation des Exploitations agricoles (PCAE). Farmers often have questions about the compliance of their facilities, the measures needed to meet regulations, and how to successfully manage livestock effluents.

Key principles of these regulations include:

• Livestock effluents must not be directly discharged into the environment or mixed with stormwater systems. They must be stored, treated, or applied responsibly.
• Minimum distances must be maintained for the placement of storage or treatment facilities, as well as for effluent application.
• Minimum storage capacity requirements include 45 days under the Departmental Sanitation Regulations (RSD) and four months under the Classified Installations for Environmental Protection (ICPE).
• In nitrate-vulnerable zones, specific capacity or agronomic requirements must be met.

Managing Livestock Effluents

The management and valorization of livestock effluents involve several steps, including proper storage, treatment, and responsible use.

Effluent Storage

Effluent storage entails safely and securely holding waste until it can be treated or applied to fields. Different types of effluents may require specific storage methods, such as buried pits, flexible tanks, covered or uncovered manure pits, phase separators, etc. Storage capacities must comply with regulations to ensure effluents are not improperly released into the environment.

Effluent Treatment

Effluent treatment aims to reduce their pollution potential and valorize certain components. Various treatment processes are used, such as anaerobic biodigestion to produce biogas, solid-liquid separation, filtration, clarification, nitrification, and denitrification. Treatments can be chemical, biological, or physical, depending on the type of effluents and pollution reduction goals.

Effluent Application

Application involves the controlled distribution of treated effluents on fields as natural fertilizers for crops. This requires a detailed application plan considering the chemical composition of the effluents, crop needs, and regulations on minimum distances from watercourses, residences, and other sensitive areas. Application must be managed to avoid soil saturation and effluent runoff into water bodies.

Economic and Environmental Benefits

Valorizing livestock effluents offers economic benefits by transforming waste into revenue sources, such as selling renewable energy or natural fertilizers. It also reduces environmental impact by minimizing soil and water pollution and contributing to greenhouse gas emissions reduction.<