Design Review Checklists
Soil Quality Restoration
New construction often involves mass grading and traffic by construction equipment, which typically leaves soils in new development areas compacted and unable to absorb much rain. Soil quality restoration at new development sites involves de-compacting (i.e. tillage to shatter compacted soils) and incorporation of compost to increase the organic matter content of the soil. On existing lawns, deep tined aeration is performed to create "macro-pores" or holes that allow water to move down into the top 6-8 inches of the soil profile. Then a shallow layer of compost is spread to increase the organic matter content of the soil.
Organic matter helps the landscape absorb rain. For each percent of organic matter the landscape should be able to absorb about 0.6 of an inch of rain. People are encouraged to "Strive for Five" percent organic matter content which should help the landscape absorb 3 inches of rain without shedding runoff. Historically, 99% of rainfall events have been less than 3 inch events. Soil quality restoration on both the urban and agricultural landscapes offers the greatest opportunity for increasing water holding capacity over the largest area, for the least cost and in the least amount of time compared to most best management practices.