Page 23 - Section4.1.1-SWPPPCutSheet-FiltrexxSedimentControl

346 | Filtrexx ® Low Impact Design Manual | Version 8.0

Look for the Filtrexx ® Certifed tm Installer Seal.

3. Runoff diversion will be placed at locations indicated on plans as directed by the Engineer.

4. Runoff diversion shall be installed above and adjacent to areas of unprotected soil or areas prone to soil erosion.

5. Runoff diversion shall be installed where 5 ft (1.5m) of the end at highest elevation shall be pointing upslope and into any existing vegetation.

6. Runoff diversion shall be installed so the trailing end of the device points down slope to prevent ponding of runoff.

7. Runoff diversion shall lead sheet and shallow concentrated runoff from vegetated/stabilized soil areas to stabilized channels, vegetated areas, level areas, high infltration zones, or collection ponds.

8. Runoff diversion shall be placed on slopes 1% or greater to allow effective runoff conveyance and to prevent ponding.

9. Runoff diversion installed on slopes > 5% may require erosion control/soil stabilization practices where runoff fow is concentrated or conveyed.

10. Runoff diversion should not be used on slopes greater than 2:1.

11. Stakes shall be installed through the middle of Runoff diversion on 10 ft (3m) centers, using 2 in (50mm) x 2 in (50mm) x 3 ft (1m) wood stakes.

12. Staking depth for sand and silt loam soils shall be 12 in (300mm), and 8 in (200mm) for clay soils.

13. If the Runoff diversion is to be a permanent runoff diversion device or part of the natural landscape, it may be seeded at time of installation for establishment of permanent vegetation. The Engineer will specify seed requirements.

14. Loose GrowingMedia tm used for backflling and extension of flter strip may also be seeded. The Engineer will specify seed requirements.

INSPECTION and MAINTENANCE

Routine inspection should be conducted within 24 hrs of a runoff event or as designated by the regulating authority. Runoff diversion should be regularly inspected to make sure they maintain their shape and are adequately diverting storm runoff. If ponding becomes excessive, additional Runoff diversion may be required, sediment or debris removal may be necessary, or the device may need to be adjusted to allow gravitational fow of water down slope. A freeboard height of 4 in. (100mm) below the top edge of the device must be maintained at all times. Runoff diversion shall be inspected until

the entire area has been permanently stabilized and construction activity has ceased.

1. The Contractor shall maintain the Runoff Diversion in a functional condition at all times and it shall be routinely inspected.

2. If the Runoff diversion has been damaged, it shall be repaired, or replaced if beyond repair.

3. The Contractor shall remove sediment and debris at the base of the upslope side of the Runoff diversion when accumulation has reached 1/2 of the effective height of the Soxx tm , or as directed by the Engineer.

4. A freeboard height of 4 in. (100mm) below the top edge of the device must be maintained throughout the life of the device.

5. Runoff diversion shall be maintained until the hill slope has been permanently stabilized and construction activity has ceased.

6. GrowingMedia tm will be dispersed on site once disturbed area has been permanently stabilized, construction activity ceased, or determined by Engineer.

For projects exceeding 1 year, Runoff diversion can be seeded at the time of installation to create a permanent runoff and erosion control system. Vegetation will add stability to the device and will reduce UV degradation of the system. The appropriate seed mix shall be determined by the Engineer.