Land grading and excavation ensure proper drainage, which is vital for all sites. The highest point of the land should start at a structure’s exterior, moving down to direct rainwater away from the building’s foundation. When teams perform land grading, they reduce negative drainage and ensure positive drainage. The guide below explains what these terms mean to help you understand the importance of this service.

What Is Negative Drainage?

This refers to the slope that moves toward the building. When the structure is at a low point, water can pool in the area and cause ground erosion, which leads to foundation sinking and cracking over time.

Negative drainage can be created by landscaping. For example, if landscapers add soil to an area, the added slope can block drainage and make rainwater accumulate. To prevent foundation damage and moisture issues, you may need to have soil moved to change the slope after landscaping work.

What Is Positive Drainage?

This refers to the slope needed on a building site, which is responsible for moving water to the property’s lowest elevation point. The first step in site excavation is to move soil around to create this slope.

With proper positive drainage, you avoid moisture issues in the building’s basement and foundation. Downspouts also properly direct water away when it rains. Most municipalities require slopes of at least six inches in the first 10 feet around the building.

If you notice water pooling after land grading, contact an excavating contractor to assess the land and re-grade if needed to meet standard measurements. Additionally, have gutters and downspouts cleaned twice a year to ensure they direct rainwater at least 10 feet away from the facility. 

When you need excavation in Salisbury Mills, NY, call Black Rock Excavating Corp. They provide a range of services to prepare sites for building, including land clearing and excavating. They also install foundation drainage systems and basement waterproofing solutions to protect properties from water damage. Call (845) 649-1882 for a quote, or visit them online for a look at their work with drainage systems.