Update: The Pennsylvania Manual Revision Committee (now renamed Pennsylvania Stormwater Technical Workgroup) met formally for the third time on Thursday, April 8, 2010 at the PADEP Lab in Harrisburg, including approximately 30 attendees.  Dr.Rob Traver, director of the VUSP chaired the meeting, as he has done in the past, with PADEP SE Region stormwater chief, Domenic Rocco, acting as chief note taker. Although PADEP regional office staff were well represented, PADEP Central Office/Headquarters staff are not participating.  The Workgroup has been divided into nine sub-groups focusing on major technical/substantive issues in the existing Stormwater BMP Manual.

Previous meetings had been devoted largely to organizational/administrative issues of the group  - how to make decisions, Workgroup eligibility criteria, formation of a Leadership Board or board of directors, etc..  After a quick vote of confirmation by the Workgroup members, Sub-Groups launched into their progress reports.  Although some Subgroups had not been able to meet and make much progress, several Subgroup reports were both substantively detailed and powerful.  From Infiltration to Water Quality to Methods to Control Guidelines, sub-group reports included impressive data gathering from other states, other sources, typically expanding on existing Manual content. Some highlights:

There was an especially detailed report from Infiltration (Russ Losco, soil scientist) on better soil testing methods, demonstrating that an enormous amount of progress in thinking/understanding has occurred since similar discussions/arguments occurred in the Rachel Carson Bldg yrs ago when the current Manual was being prepared.

Michele Adams talk about Methods Subgroup discussions, reflecting once again the progress in stormwater “science,” including use of continuous simulation modeling, focus on smaller storms, and the like.

Frank Browne and Shirley Clark talked about complexities which the Water Quality Subgroup is wrestling with, again an impressive discussion which suggests a need for making Manual guidance more sophisticated, more complex.  A major issue affecting Manual revisions here seems to be PADEPs revisions to Chapter 102 which, for good or bad, are providing some sort of “anchor” for stormwater management in Pennsylvania municipalities.

There’s much more to add.  Subgroups were directed to review the existing Manual and provide any editorial changes by the end of May.  By the end of June, Subgroups should provide a scope of work which provides an outline for the changes to the technical provisions of the Manual.  Although the Subgroups continue to meet on a monthly basis, the next workgroup meeting will be on July 14 at Villanova University.  Of course, the huge challenge facing the Workgroup will be moving from development of critically good ideas into readable Manual form which is so time consuming and challenging for a volunteer effort…

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As reported previously here, the PADEP-organized effort to revise its Stormwater BMP Manual (2006) re-convened for an almost day-long session at the South Central Regional Office in Harrisburg on 12/15/09.

The Manual Revision Committee met once in September and has resulted in the formation of 9 sub-groups. Each sub-group was assigned a specific substantive topic, and continued meeting during the Fall.

The appropriateness and transparency of this process has been questioned.  As a result (and also for budgetary reasons), PADEP has reduced its direct sponsorship of the now all-volunteer Committee. To the extent that PADEP staff continue to participate, they do so on their own time.

The intent of the December 15 meeting was to summarize and review sub-group findings and determine future actions.  Dr. Robert Traver from Villanova University had been asked by PADEP to chair the meeting, rather than PADEPs Domenic Rocco, the Committee’s initial organizer and coordinator.  About 30 attended, including several staff from regional PADEP offices (PADEP Central Office staff have been directed not to participate; however, regional office are free to participate as they see appropriate).

Some major actions included:

1.  Re-Constituting the Group:  considerable time was spent in re-affirming the existence of the group and establishing an organizational structure

• including its separation from PADEP
• to be called a “stormwater technical work group”

2..  A mission statement was defined, expanding future work beyond Manual editing to include all related aspects of PADEPs stormwater management program

• its primary focus is to be “technical”
• but the group work also is likely to include aspects of policy (the group seems to feel that a technical focus invariably involves weighing in on policy issues such as recommended control guidelines or standards, as well as other important issues like Chapter 102 Revisions or the pending Draft MS4 General Permit and others)

3.  Goals were defined

• Manual editing, both simple and complex
• possible comment on Chapter 102 Revisions and Draft MS4 General Permit program and others

4.  Membership in the group was given some definition

• additional representatives can be added with submission of a resume, etc. provided that any/all focus on the “technical” work and agree to work cooperatively

5.  Roberts Rules of Order will be used

6.  The work group will have a board composed of the existing chairs of each of the 9 existing sub-groups; without establishing more complex by-laws, this board will meet and decide whatever needs to be decided

7.  In terms of group outputs, “minority opinions” will be included when substantive disagreements emerge

8.  No end or completion date was established.

Sub-group reports were given, mostly in verbal form but some with written attachments (to be included in the minutes of the meeting).  Some highlights include:

Control Guidelines - Rob Traver stressed that CGs interrelate with so many of the other sub-groups.  Thus far this sub-group is thinking that there…should be a collection of CGs rather than the more prescriptive Manual approach which is probably limiting use of LID at sites

Calculation Methods - The point was made that given the enormous shortcomings of rational, soil cover complex, and related methodologies, continuous flow modeling is likely to be the preferred way to go, though it is frustratingly data intensive and difficult to make happen across Pennsylvania’s 2550+ municipalities.  Furthermore, this method isn’t compatible with event-based standards such as CG1 and its 2-yr storm.  The methods are related to the standards that are being recommended!

Vegetated Systems - This sub-group is arguing for explicit Standards of Practice so that explicit engineering standards can be applied at sites.

Capture/Re-Use - This sub-group has substantially expanded the definition of this BMP from the current Manual.

Water Quality - This sub-group wants to establish water quality standards which transcend the current Manual, especially in light of new standards being promulgated for the Chesapeake Bay by EPA and others.

Infiltration - The major focus of this sub-group has been revising the appendices dealing with soil testing and site testing.

The Redevelopment and Highways and Maintenance sub-groups provided very condensed reports.

StormwaterPA will continue to report on this important effort in future weeks as it continues to evolve.

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In recent weeks, we have reported in considerable detail on the process to revise the existing Pennsylvania Stormwater Manual (released in December 2006).  PA DEP formed a Revision Committee, including nine sub-groups which focus on different topics (e.g., stormwater standards, water quality, and so forth). As we understand it, these sub-groups are continuing to meet this Fall.

However, at the state level, we also understand that PA DEP - at least for the moment - is pulling back from this effort and re-considering its role in terms of this revision process, to some extent reflecting the severe cutback in budget funding that has just been enacted.  PA DEPs remarkable 27 percent budget cutback is requiring PADEP to re-evaluate its agency workload, including any projects such as Manual revision which are not absolutely essential.

Secondly, PA DEPs support for the Revision Committee also is being re-evaluated as the result of input the agency has received in recent weeks which questions the extent to which this revision process adequately represents a broader public participation effort with all stakeholder groups and perspectives.  Note that the existing Manual had been developed with a large representative Oversight Committee, which met frequently during Manual development to provide input into the process.  As we understand it, much of the discussion relates to whether sub-group revisions are simply technical updates - new information on BMP development, for example - and correction of Manual errors - versus changes to recommended stormwater standards (control guidelines) and management policies.  This line quickly blurs.  We’ll try to keep you informed as this effort progresses…

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As previously noted in our September posts, PA DEP has convened a BMP Manual Revision Committee. In their notification to attendees, they noted that

Much has been learned since the release of the manual and it is a goal to capture as many stormwater situations as possible. However, it is also understood that it is not practical to capture all situations…

… recommended updates may include edits to existing portions, complete omissions, or additions of new material.  All changes much be justified through acceptable principles of engineering or science.  If unable, to do so, subgroups may bring new ideas before the bigger committee for consideration and feedback.

Following, and in a series of consecutive posts, we will outline the focus of each Sub-Group as presented at the first Commitee Meeting

A. Subgroup Topic:  Alternate Control  Guidelines

CG-1 will likely remain, as currently established, for projects located within Special Protection Watersheds.  Recommendations for change, however, will still be considered.

The key is to find whether there are other acceptable guidelines that are protective to receiving streams and that can stand the test of scrutiny.

Ideas thrown out so far:

1. 1-year, 24-hour storm for non-Special Protection &  non-SW impaired streams
2. Revisit CG-2 for projects greater than 1 acre. (with added detail analysis/routing for peak control)
3. Matrix or Tiered Approach based on Watershed Characteristics:
   1. Stream Order
   2. Special Protection
   3. Stream Impairments
   4. Public Drinking Water Supply
4. PWD Model
   1. Water Quality -which includes GW Recharge  (1 inch from DCIA)
   2. Channel Protection (ED of 1-yr 24 hour for DCIA, Q<0.24cfs/ac; 24 to 72 hrs)
   3. Flood Control  (Act 167 or default Rate Control for 1 through 100 year storms)
5. A hybrid of those listed.

Questions:

Do we need to come up with a separate CG for streams impaired by stormwater?  (i.e. TMDL compliance)

It has been argued that CG-1 is overly conservative, particularly when a meadow assumption is used for existing conditions.  Does the subgroup agree/disagree?   What changes would the group recommend?

Does the group believe that a tiered or regionalized approach is necessary due to the diversity of Pennsylvania regions and watersheds?  Does the group believe it is feasible?

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