Reducing Nonpoint Source Pollution: Strategies For A Cleaner Environment

Nonpoint source pollution is a complex issue that stems from various sources and locations, making it challenging to address. This type of pollution arises when rainfall or snowmelt moves across the ground, picking up and carrying natural and human-made pollutants into water bodies like rivers, lakes, and wetlands. While it is difficult to pinpoint a single source of nonpoint source pollution, the collective impact of these diffuse sources is significant, particularly on water quality. As experts strive to understand and mitigate this problem, several strategies have emerged to reduce and prevent nonpoint source pollution, with a focus on urban, suburban, and agricultural settings.

Properly dispose of oil, grease, and chemicals

Nonpoint source pollution is a leading cause of water quality issues, and it is essential to take measures to prevent it. One critical aspect of reducing this type of pollution is the proper disposal of oil, grease, and chemicals. Improper disposal can have detrimental effects on plumbing systems, the environment, and water quality. Here are some detailed guidelines for responsible management:

Cooking Oil and Grease:

The disposal of cooking oil and grease should never involve pouring them down the drain or toilet. When disposed of incorrectly, these substances can solidify and clog pipes, leading to costly repairs and sewage issues. Instead, follow these steps:

• Allow the oil or grease to cool completely.
• Choose a suitable container, such as a glass jar, a waxy container (e.g., milk carton), or a dedicated grease container. Ensure the container can be tightly sealed and won't leak.
• Transfer the cooled oil or grease into the chosen container.
• Seal the container tightly to prevent spills.
• Dispose of the sealed container in your household trash. Alternatively, you can take it to a recycling centre.
• For small amounts of vegetable oil, you can add them to a compost bin in minimal quantities.

Motor Oil:

Motor oil should also never be poured down household or street drains. Instead:

Take your used motor oil to a service station. By law, they are required to accept up to five gallons of used motor oil per person per day, free of charge.

Household Chemicals:

The disposal of household chemicals requires extra care to prevent environmental contamination:

• Do not pour chemicals down storm sewers or drains.
• Utilise local toxic drop-off sites or community programs for collecting household hazardous waste.
• Clean up any spills, such as brake fluid, oil, grease, or antifreeze. Do not hose them into the street, as they can eventually reach local water bodies.
• Support initiatives for proper chemical disposal in your community by requesting local government action if necessary.

Maintain septic tanks

Maintaining your septic tank is an important step in reducing nonpoint source pollution. Septic systems can be a major source of water pollution, so ensuring your septic tank is functioning properly is crucial.

Septic tanks, like any other tool or appliance, require regular maintenance to function effectively. They are designed to separate solids, greases, and liquids, with bacteria breaking down the solids and the liquid being treated as it moves into the absorption field. A properly functioning septic system should not release anything harmful to you or the environment.

To ensure your septic system is working as it should, follow these maintenance tips:

• Have your septic system serviced regularly, including pumping the tank every 2-5 years, depending on household size.
• Inspect the tank for leaks to prevent excess sewage from entering the drain field and reducing the system's effectiveness.
• Conserve water in your household to prevent the septic tank from overfilling. Every flush of the toilet sends an equal amount of water into the drain field.
• Only deposit necessary waste down your drains. Avoid using garbage disposals with a septic system, as they can lead to an excess of solid materials in the tank.
• Do not flush tissues, feminine hygiene products, or diapers down the toilet, as these can quickly clog the system.
• Avoid using detergents or additives, as these can clog the perforated pipes in the drain field and potentially kill the helpful bacteria that break down waste.
• Prevent compacting the soil covering your septic drain field, as compacted soil becomes ineffective and cannot be restored.

By following these maintenance steps, you can help ensure your septic system is functioning properly and does not contribute to water pollution.

Reduce livestock impact on water quality

Livestock have a significant impact on water quality, and there are several ways to reduce this impact.

Firstly, it is important to prevent livestock from directly accessing water bodies such as streams and rivers. Livestock can trample the stream bank, deposit faeces, and increase E. coli levels. Fencing off water sources and providing alternative drinking water sources are effective ways to achieve this. Implementing a rotational grazing system is also beneficial, as it reduces pasture erosion and allows vegetation time to grow.

In addition to managing livestock access to water, it is crucial to consider their water quality requirements. Good water quality and cleanliness can increase water intake and improve livestock production. Water quality can be affected by various factors, including total dissolved solids, salinity, pH levels, and the presence of microorganisms and chemical contaminants. Regular testing of water sources is recommended, especially for shallow water sources, during droughts, or when there are concerns about water quality.

Furthermore, the use of a "watering system" can be advantageous. This system prevents livestock from directly accessing streams or ponds, protecting the water resource and promoting more uniform grazing. By managing the available water and strategic tank placement, farm managers can increase pasture productivity and nutrient distribution throughout the field.

Additionally, proper management of livestock waste is essential. Manure should be stored properly, and nutrient management practices should be implemented to minimise the impact on water sources. This includes applying fertilisers sparingly and according to the needs of the soil to prevent excess nutrient runoff.

By implementing these measures, it is possible to significantly reduce the impact of livestock on water quality, contributing to improved environmental conditions and livestock health and productivity.

Use buffer strips to limit soil loss

Buffer strips are strips of grass or other permanent vegetation planted between impervious paving materials (such as parking lots and sidewalks) and a body of water. They can also be planted between agricultural fields and the watercourses they drain into. The buffer strip absorbs soil, fertilisers, pesticides, and other pollutants before they can reach the water.

Buffer strips are designed to intercept runoff and are usually used in conjunction with other erosion-control practices. They are placed in a variety of locations within a landscape, such as along steep slopes, at the edge of fields, or adjacent to streams, ponds, or wetlands. The type of vegetation and spacing of buffer strips depend on site-specific conditions. For example, perennial grasses are typically planted along steep slopes within contour buffer strips.

Filter strips are a type of buffer strip that provides increased infiltration and removes sediment from overland flow. They are located at the edge of fields or adjacent to water sources and do not interfere significantly with normal farming operations. Areas with gentle slopes are the best locations for filter strips.

Riparian buffer strips are planted immediately adjacent to water sources to stabilise riverbanks, provide inputs to freshwater systems, and stabilise water temperatures. They can also help to reduce the risk of flooding and improve the microclimate in terms of temperature and humidity. In addition, they provide habitat for a range of plant species and related insect, bird, and mammal species.

To maintain their performance, buffer strips require periodic maintenance. In agricultural settings, buffer strips can be designed with multiple zones of different vegetation types to optimise their effectiveness in mitigating pollution. For example, a combination of a narrow strip of native trees, a wider zone of croppable native tree species, and a narrow zone of dense grass or similar vegetation can effectively trap sediments and pollutants.

Apply best management practices for fertilizer

Applying best management practices for fertilizer is crucial to reducing nonpoint source pollution. Here are some detailed instructions to achieve this:

Understand the Impact of Fertilizers on Water Quality

Recognize that fertilizers are a significant contributor to nonpoint source pollution. Excess fertilizers from agricultural lands and residential areas can contaminate lakes, rivers, wetlands, and coastal waters. When fertilizers are applied inappropriately or in excess, they can be washed away from lawns, fields, or streets into water bodies through stormwater runoff. This contributes to nutrient pollution, which can have harmful effects on aquatic ecosystems and drinking water supplies.

Perform Soil Testing and Crop-Specific Calibration

Before applying fertilizer, conduct soil testing to determine the specific nutrient needs of the soil. This ensures that fertilizer applications are modified to meet those needs without exceeding them. By avoiding over-application, you can reduce the risk of excess nutrients running off into nearby water bodies. Crop-specific calibration further refines fertilizer application by taking into account the unique nutrient requirements of different crops.

Practice Conservation Tillage

Conservation tillage, also known as reduced tillage, involves leaving crop residue from a previous harvest when planting a new crop. This technique helps to reduce erosion by minimizing soil disturbance. With conservation tillage, the soil surface remains undisturbed from harvest to planting, which reduces runoff. It also improves soil health by building up organic material, enhancing water retention, and providing a protective cover that shields the soil from erosion.

Adopt Cover Crops

Utilize cover crops between growing seasons to uptake any residual nutrients left in the soil after the harvest of the main crop. This helps to reduce nutrient runoff by minimizing the amount of excess nutrients in the soil. Cover crops also contribute to improved soil health by adding organic material and protecting the soil surface from erosion.

Implement Vegetated Buffer Strips

Establish vegetated buffer strips, also known as riparian corridors, around fields and streams. These buffer zones, planted with vegetation, act as natural filters by intercepting and absorbing fertilizers and other pollutants before they reach water bodies. A well-established riparian corridor can also help regulate water temperature and protect the stream bank from erosion. The width of the corridor can be adjusted based on its intended use and the surrounding land use.

Explore Alternative Irrigation Methods

Consider using drip irrigation instead of furrow irrigation. Drip irrigation delivers water directly to the plant's root zone, reducing water loss to evaporation or runoff. This method also allows for better control over the amounts of pesticides and nutrients added to the irrigation water, minimizing the risk of excess nutrients reaching water bodies.

By following these best management practices, you can effectively reduce nonpoint source pollution caused by fertilizers. These practices not only benefit the environment but also contribute to more efficient and sustainable farming practices.

Frequently asked questions