Your house roof, like pavement, sheds water. If downspouts from roof gutters empty out on grassy areas, the water will have a chance to soak naturally into the ground. This will allow the water that runs off your roof to have a chance to soak into the ground and not simply run off (Source: Arkansas Home*A*Syst). Preventing too much run off reaching the stream can help to reduce the severity of problems such as erosion, flooding, and logjams (woody vegetation which obstructs a stream channel). Removing logjams and was a labor intensive aspect of streamside property management for the landowners we interviewed. While some logjams that are creating problems such as flooding and erosion will need to be removed it may be beneficial to both the stream and landowners to let others remain since some log jams may actually serve important functions by helping create various habitats (i.e.,, riffles, runs, and pools) and serve to restore stream nutrients. For instance woody debris that is embedded in a streambank or bottom should not be removed (A New Way: Restoring Habitat in Urban Watersheds, Wayne County Michigan DEQ, http://www.mi-wea.org/docs/MBest_WDB(A).pdf).
Photo credit: http://makingafarm.wordpress.com
Infiltration allows run off water from rain, storms, your garden hose, etc. to soak into the ground instead of running into nearby streams, picking up pollutants and sediments on its way. It also prevents problems associated with too high of water flow in streams, including erosion, flooding, and logjams.
Time and direct cost of landscaping to promote infiltration.
Review the ODNR fact sheet Stream Debris and Obstruction Removal on log jams to understand more about them and when removal is needed:
http://www.dnr.state.oh.us/water/pubs/fs_st/stfs18/tabid/4173/Default.aspx. For roofs without gutters, you can plant grass, spread bark mulch or use gravel under the drip line to prevent soil erosion and increase the ground?s capacity to absorb water. Many home lawns are sloped to encourage water to run off instead you could provide low areas landscaped with shrubs and flowers, adapted to temporary wet conditions, where water is encouraged to soak into the ground (link to FSWCD plantings fact sheet). Concrete and asphalt roads, driveways and walkways prevent rainwater from soaking naturally into the ground. When you have the choice, consider alternatives such as gravel, wood-chip or brick walk on driveways or patios. Where you need a more solid surface, consider using a ?porous pavement? made from porous concrete, interlocking cement blocks, pavers, or rubber mats that allow spaces for rainwater to seep into the ground. If you do pour concrete, keep the paved area as short and narrow as possible.
Review the list of trees, shrubs, grasses recommended for preventing erosion and stabilizing an urban streambank.
A New Way: Restoring Habitat in Urban Watersheds, Wayne County Michigan DEQ, http://www.mi-wea.org/docs/MBest_WDB(A).pdf
ODNR Stream Debris and Obstruction Removal