There was an error in this gadget

Friday, December 11, 2009

Post Construction Stormwater BMP Trading / Offsets

Lets Fix the Chesapeake Bay, Help the Building Industry and the Economy!

There are times in life when you need to look long and hard to see the light at the end of the tunnel.  This seems to be one of those times.  With DEP  enacting numerous new regulations, EPA developing a bay wide TMDL, DEP & Conservation District budgets and staff cuts and the building industry still trying to recover, we see opportunities that would otherwise not be presented. We have proposed solutions to the Pa. Conservation District, the Chesapeake Bay Foundation and DEP, that help solve environmental and development problems to help in fixing the Chesapeake Bay.  First, let’s look at the main source and location of pollution to the bay.

These figures show that the highest levels of nutrients, shown in red are generally located in south central Pennsylvania.  Looking at Google earth aerial photos we see numerous farms with little or no buffer to streams in these same areas.

What does this have to do with the building industry?  Well as part of DEP’s & EPA’s efforts to clean up the Bay we have numerous new regulations which require Post Construction Stormwater Best Management Practices (PCSW BMP’s) in site designs that will be difficult to comply with and will require a substantial amount of money to design, install and maintain.  A much more effective pollution control measure would be for the building industry to help fund the off site stream buffers in return for offsets of certain PCSW BMP site requirements.  Of course we would still need to install all erosion and sedimentation control measures and stormwater facilities to control the runoff rate to pre-development conditions.  We would propose to offset stormwater infiltration areas, that will be a long term problem for everyone to guarantee maintenance and function, with off site forested buffers.
In the front of this article we show one of our recent site designs with the infiltration areas colored in orange.  These areas are  typically designed to hold one foot of water which will infiltrate into the ground after a storm event.  We see these areas as a problem for home owners and source of complaints to builders.  After the development is completed a property owner is likely to fill in these areas with topsoil to eliminate the ponding after each storm.  This will be a difficult issue to police.
Instead of designing and installing the infiltration areas we would propose that the builder or designer work with the Conservation Districts to identify riparian forested buffers or similar  projects that need funding. This would be similar to the wetlands banking concept we have used in the past. EPA & DEP has identified the farms as a major contributor to nutrient pollution, however, they have not  come up with a way to enforce or fund the problem.  We see a mutual benefit to the builders, farmers, DEP, EPA and Conservation Districts to cooperate and help provide a source for funding of these projects.  This would maximize the environmental benefits for a reasonable cost and minimize the long term maintenance and enforcement issues.
Farmers would need to grant a conservation easement along the stream in return for technical assistance to bringing the farm into compliance and installation of the riparian buffer.  It may be possible to generate and sell nutrient credits with this program which could benefit the farmer and/or the Conservation District with long term funding.
Please consider this proposal and e-mail your comments if you feel this is the right way to go.  We are actively promoting this concept to DEP, EPA and the Conservation Districts.  Your input would be helpful to make sure we get this right. Any cost and maintenance issues you have had with stormwater BMP’s would also be  helpful to note.

For more information on Land Development Issues & Solutions see our website at


  1. Dear Mr. Fisher:

    There are plenty of nutrient credits listed for sale already. I think the problem is that buyers (POTWs) need assurance that the credits are long-term, fixed price and enforceable. If you'll send me your email address (I can't find it on your blog or website), I'll send you my ideas on how this could be achieved.


    Pat O'Connell

  2. This is well-thought out, Bob. I am generally NOT in favor of the concept of trade-off mitigation, preferring that each contributor mitigate their own contribution to a given problem. However, your approach goes to correct the injustice of the disproportionate focus our Commonwealth has placed on private land development. Having spent much of my career investigating stream impairments in PA, I know that said impairments are caused (in order of severity) by Agricultural Runoff, Mine Drainage then by Public Roadway Runoff. Degradation from private land development comes in a distant 4th. But most remedial & permitting activities seem to burden private development activities disproportionately to their contribution. Given this undeniable situation, your proposal seems, in this case, appropriate. It would allow a win:win:win for the Ag community, the Development community and the environment. My first concern is for the environment, but I am also concerned with fairness to the economic community, which funds these remedial actions. I would support your proposal. Keep thinking.

    --Steven Todd, PE, LEED AP

  3. Thanks for your comments Pat & Todd,

    I 100% agree with your comments on why the POTW's have not used credits yet. If fact that is why the Fair Share Coalition ( Pa. Builders, Chesapeake Bay Foundation, Pa. Conservation Districts, & Pa. Municipal Authorities Assoc.. The Pa. Farm B. was a member but then dropped out) was originally formed. I have been part of that coalition from day one and when you can get that many groups all agreeing on anything you know there is something really wrong with where DEP was going.

    The whole point of my proposal is not so much to generate credits as it is to allow new construction to do more effective environmental controls off site instead of the infiltration areas on site that will cause sinkholes and complaints from residents. If we develop a corn field we could actually generate NPS credits just by the change in land use. We are required by regulation to assume that the farm field is in good meadow conditions and then use that as our pre development assumption which is not true. The next part of the NPDES, Post Construction Stormwater Permit requires that the difference in pre to post two year storm volume be infiltrated on site. I have had to do infiltration on sites underlaid with limestone and on sites with high ground water just to get the permit approved even though I strongly disagree with this as the design engineer who is sealing the plans. A relatively new policy of the department is requiring sites that need to get a permit renewal to meet the new stormwater infiltration requirements. This could cause a total site redesign and lost of units on projects that may of only started. DEP has also changed the rules on the time frames for NPDES permits just last week, they were 5 year permits now they are 2 yr. permits.
    The Pa. Conservation Districts supports my plan as it provides a funding source to address the pollution from the smaller farms that are not covered under the CAFO regulations. Go to google earth and follow the major streams just north east of Lancaster to see how may farms have no buffers what so ever adjacent to streams. This is a major problem that is not being addressed by the current nutrient trades that just ship manure out of the drainage area. A Forested Ripirian buffer will provide a long term, reliable and relatively cheap nutrient credit that the STP's could purchase with out much risk.
    I will be discussing this proposal with the Fair Share Coalition and DEP next week so mabey we can get some real progress done on fixing the bay and help get our economy going by helping the housing industry. Have you noticed that the federal, state and local governments are all cutting their budgets and the budgets of the Conservation Districts? Housing is one of the few things we still make in this country and it is critical to getting our economy and jobs going again. So I say Save the Bay and save Housing at the same time.


  4. Anyone have any luck using curb inlet filters?