La Porte, TX Environmental Rules: Grading & Drainage (2026)

La Porte's grading and drainage regulations ensure that land development does not increase flood risk or divert stormwater onto neighboring properties. Property owners may not grade, fill, or alter their lots in a way that changes established drainage patterns to the detriment of adjacent properties. For new construction or substantial improvements, a drainage plan must be submitted as part of the building permit application showing existing and proposed grading, drainage flow paths, and any retention or detention features. The plan must demonstrate that post-development runoff does not exceed pre-development rates. The city may require on-site detention for larger projects. La Porte is within the jurisdiction of the Harris County Flood Control District, which sets watershed-level drainage standards and maintains regional channels and detention basins. Development within FEMA-designated floodplains is subject to additional restrictions on fill and grading under the flood damage prevention ordinance. Drainage must be directed to the city's storm sewer system or approved drainage channels, not to the sanitary sewer system. Driveway culverts and drainage structures within the public right-of-way require city approval. Given La Porte's flat topography, clay soils, and high water table, proper grading is critical to preventing standing water and foundation damage. The city's Public Works department oversees drainage infrastructure and may inspect private property grading that affects public drainage systems.