Waterwise Wednesday: Permeable Pavement

Permeable pavement allows water to pass through the surface into the ground generating more groundwater recharge, faster melting of ice and snow, and decreasing the amount of water runoff from a property. Porous concrete, porous asphalt, or interlocking pavers are also good for trees whose roots can access the air and water that flow through the pavers.

Photos: (Top) Demonstration of porous concrete. (Bottom) Water runoff comparison of permeable asphalt and standard concrete.

Construction Bulletin April 2016

Comments Wanted on New Construction Storm Water Permit 

On Friday, March 25  the draft for the new Construction Storm Water (CSW) Permit was sent to EPA to start the 90 day review period, following which will be the formal public notice period.  Nebraska Department of Environmental Quality is requesting initial comments and feedback before the permit goes out for public notice. Any responses are appreciated before Monday, May 16th.  download

A summary of changes is inlcuded here:  NDEQ CSW General Permit_Fact Sheet

The permit draft may be reviewed here:  NDEQ CSW_General Permit

  Policy changes to the permit include:

  1. All forms must be submitted electronically on the NDEQ website. Paper forms for NOIs, CSW-Transfers, and NOTs  are no longer accepted.
  2. Oil and gas field activities or operations will now require a permit.
  3. Coverage of existing permits has been extended from 90 to 180 days before reapplication is needed under the proposed general permit.
  4.  Permit numbers have been changed to correspond with anticipated issue year.

Responses can be sent to either  Emma Trewhitt, NPDES Permits and Compliance Unit or the permit writer, Patrick Ducey.   Emma can be contacted at Emma.Trewhitt@nebraska.gov or 402-471-8330. Patrick can be reached at patrick.ducey@nebraska.gov or 402-471-2188.

Construction Bulletin April 2014

Goals for Construction Site Runoff Management

Ahh, Spring— warmer weather, thawing ground, and afternoon rain showers.   While welcoming the change of season,  it’s also time to consider Best Management Practices (BMPs) for keeping the soil on site and preventing stormwater run off and sediment pollution.

The ultimate goal for construction site runoff management is to prevent the pollution of stormwater runoff.  Best Management Practices (BMPs) aim to slow the velocity, control the volume, and/or  filter  site run– off.  Stormwater permits require BMPs to address erosion and sediment run-off, soil exposure, ground disturbance, compaction,  buffers,  outlet protection, and stabilization.  Below are some BMPs to consider for construction sites.

Grass

Stabilization, or planting ground cover,  allows run off to infiltrate the ground providing nutrients to the plants and replenishing ground water. Stabilization is required by the Nebraska general construction permit as soon as practicable on sites and no more than 14 days after construction activities have ceased.

 

Slope Drain

When the slope is steep channeling the runoff through a slope drain can be an effective erosion control.  Drains may be made of pipe,  s shown, or a constructed channel lined with rock,  turf replacement mats,  and wattles to slow the flow of water.

 

Flexible Gutter

Flexible rain gutters can direct roof water away from exposed soil.  The gutters can channel water to impermeable areas (e.g. concrete driveways) where clean stormwater can run to the gutter or to vegetated areas where plants and soil can absorb the water

InspectionRegular inspection,  every 14 days and within 24 hours of a 1/2” rain event,  is the best way to insure construction site BMPs are working effectively.  Look for evidence, or  potential,  of pollutants entering the drainage system.  An inspection report must be identify any incidents of non-compliance with permit conditions and actions taken to correct the issue.  If no incidents of non-compliance were found, the report must contain a certification that the site is in compliance with the Storm Water Pollution Prevention Plan (SWPPP). The  reports should be retained with the SWPPP for up to three years after the permit expires or is terminated.