top of page

Reducing Water Runoff With Compost

In the quest for sustainable environmental solutions, compost has emerged as a star performer. Its application in stormwater and erosion control projects offers impressive benefits that extend beyond carbon capture. Compost, primarily composed of carbon-rich materials like wood and food waste, is an exceptional water retainer that promotes soil health and reduces the need for fertilizers. This post delves into the remarkable ways compost can aid in erosion control efforts, the methods employed, and its positive impact on the environment.

The Power of Compost in Erosion Control

According to experts, compost proves to be an invaluable asset in erosion control. Its coarse structure effectively diverts the impact of rainfall, minimizing the risk of washouts. Moreover, compost has an astonishing capacity to hold water – up to 27,000 gallons per acre-foot for every 1% of organic matter that is added to the soil. This abundant water retention capability addresses flooding and runoff concerns, while simultaneously reducing erosion and supporting the establishment of vegetation, which is crucial for effectively controlling erosion.

How Compost Controls Erosion

Compost employs several mechanisms to combat erosion effectively:

  1. Increasing Water Infiltration: By enhancing water infiltration into the soil surface, compost helps replenish groundwater levels and prevents surface runoff.

  2. Reducing Runoff and Soil Particle Transport: Compost acts as a natural barrier, reducing the speed and volume of runoff, which in turn minimizes the transport of soil particles and pollutants downstream.

  3. Promoting Plant Growth and Soil Cover: Compost provides essential nutrients to support plant growth, ensuring better soil cover, which stabilizes slopes and prevents erosion.

  4. Enhancing Soil Structure: The addition of compost to soil alleviates compaction and improves soil structure, enabling better root penetration and higher rates of both water infiltration and drainage.

  5. Buffering Soil pH: Compost helps maintain an optimal pH level in the soil, fostering ideal conditions for the establishment and growth of vegetation.

Infographic about the benefits of compost in runoff control

Methods of Compost Application in Erosion Control

There are two primary methods for using compost in erosion control:

1. Compost Blankets or Mats:

Compost blankets involve applying high-quality compost directly to areas at risk of erosion, such as construction sites, stream banks, and other disturbed or excavated land areas. The primary purpose of a compost blanket is to protect the soil surface until vegetation is established. It is crucial to ensure that the compost material encourages plant growth, and the slope is properly seeded following compost application.

2. Compost Filter Berms:

Compost filter berms are contoured runoff and erosion filtration structures suitable for steeper slopes with high erosive potential. These berms allow runoff water to flow while filtering out sediment and pollutants. They also slow down the flow, allowing soil particles to settle out, further reducing erosion. Compost filter berms can be planted and seeded at the time of application for permanent vegetation establishment or spread out and planted later, providing flexibility in project planning.

Compost stands out as a sustainable and effective solution for stormwater and erosion control applications. Its ability to retain water, promote soil health, and support plant growth makes it an invaluable resource for combating erosion and protecting the environment. By incorporating compost blankets and compost filter berms into erosion control strategies, we can harness the power of compost to build a greener and more resilient future.

Let’s Go Compost is a community-led effort to make compost bins free and accessible. We upcycle empty bulk ingredient bins into free, food-safe worm compost bins that are donated back to the community. Click here to get a free compost bin at our next pick up event.


bottom of page