Creative Drainage Solutions

On undeveloped land, most rainwater soaks into the ground and flows slowly to nearby lakes and streams through the soil. When land is cleared or covered with impervious surface, rainwater flows quickly across the site and can result in flooding and erosion. Speaking in small scale, although single-family homes are typically small sites, the cumulative effect of uncontrolled rainwater from these sites can be significant to downstream property and water bodies.

Due to the potential environmental damages as well as property damages that can arise from land disturbance that affects drainage patterns, most new or remodeled single-family homes creating or replacing  impervious areas are required to provide erosion control and flow control as a condition of the building permit.

Infiltration is the preferred method of flow control. It must be used as practical, unless soil or slope conditions preclude its use. A soils infiltration report prepared by a qualified septic designer or geotechnical engineer is typically required for developments proposing infiltration devices, in order to determine infiltration feasibility and rate.

Drainage plans must be prepared by a licensed professional engineer in conformance with the design criteria and standards contained in the applicable municipality’s ordinance. Depending on the expertise of the design professional, the solutions proposed could become costly. It is always recommended to discuss with the design team and the project’s owner a set of options on creative drainage solutions, starting with those that take advantage of the existing site features which typically become the most economical.

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KPROX is a small Civil Engineering consulting firm dedicated to providing high quality professional services in Silicon Valley and the San Francisco Bay Area. If you need help with your project, please contact us via phone: (650) 549-4249 or via email and we will be glad to assist you.