Reduction or prevention of surface water runoff should be the first and is often the least expensive approach to reducing drainage problems. Problems are typically created by collecting rainfall from large impervious areas and discharging the flow to adjacent pervious areas. The rapid addition of runoff to the discharge location exceeds the discharge area's capacity to dissipate the flow. Consequently, the runoff moves across your site as an uncontrolled surface flow with the ability to cause slope stability and erosion problems.
To minimize surface water flow try to reduce the amount of impervious surface around your property. If you do collect water from impervious areas, try to reintroduce the water over a large area which does not affect slope stability. A slow release of the water from a detention storage facility may also be appropriate for some properties which do not have suitable discharge areas. You should contact an engineer to investigate this option for you.
Minimizing the degree of site modification to your property may also help avoid some of the slope stability problems associated with site development. Modifications to property include: conversion of native vegetation areas into landscaped zones; driveways which alter drainage flow paths; removal of vegetation along a slope; beach access construction; regrading a property; disturbing/compacting native soils; ineffective drainage control systems; pipe discharges onto a slope; unstable earth fills; and technically unjustified bulkheading.
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