What are the key factors to consider when designing an outdoor drainage system for a residential property?

When designing an outdoor drainage system for a residential property, key factors to consider include the slope of the land, soil type, amount of rainfall, location of downspouts, and proper grading to direct water away from the house. Additionally, factors such as the size and placement of catch basins, the use of permeable surfaces, and the incorporation of swales or French drains can help effectively manage water runoff and prevent flooding.