David Bardin DDOT and the Greener Storm Water InfrastructureFebruary 11, 2012

DDOT and the Greener Storm Water Infrastructure

David Jonas Bardin, [email protected]¹

February 11, 2012

Mayor Vincent Gray, City Administrator Allen Y. Lew, and DDOT Director
Terry Bellamy want to expand DC’s green infrastructure wisely. DDOT
staff and partners learn as they move to change DC’s impervious urban
design — which could prove a blessing for managing stormwater.

DDOT streets, roads, sidewalks and alleys magnify stormwater runoff

Streets, roads, sidewalks, and alleys account for almost half of all
impervious surface in the District of Columbia1 (with DDOT responsible for
all but a small, federal fraction). DDOT paves and manages far more
impervious area in DC than anybody else.

In this pie chart of all DC impervious areas, the biggest, blue slice
is roads, etc.² (almost half the whole pie);
the smaller, red slice is all the buildings; green is all the parking
lots; and purple is everything else (e.g., private driveways).

• DDOT manages virtually all of that “Roads, etc.” slice by
  itself. In contrast, buildings have tens of thousands of owners;
  parking lots have hundreds.
• Impervious areas managed by DDOT cause runoff, overflows, and
  billions of dollars of remediation costs for which everyone else pays
  almost $300 per impervious acre per month. But DDOT pays nothing, and,
  I fear, may not think about these costs — identified as
  “externalities” by economists.

DDOT must be key to reducing run off from impervious areas just because
of its share of such areas. DDOT’s deepening expertise could advance
both quality of life and sensible management of storm water run off.

Contexts of DDOT green infrastructure initiatives

DDOT is learning about what works and what it costs to change pavement
because a DC law³ directs DDOT to promote Low
Impact Development projects (LIDs), such as rain gardens and porous
sidewalks and allets, in the public space.⁴ By
its engineering of pilot LIDs, DDOT can test cost-effectiveness and how to
avoid unintended consequences.⁵ DDOT issued an
LID Action Plan in 2010.⁶ Using ARRA funds,
DDOT removed three impervious acres during the past couple of years.⁷
That same DC law calls for improved regulation by DDOT of other people’s
projects in the public space.

Green infrastructure programs have multiple goal

People living in DC and businesses located here can benefit if less
rainwater runs off into sewers from DDOT’s impervious surfaces and more
of that rainwater soaks into the ground or evaporates (or is
“harvested” and used) — enhancing our environment with healthy shade
trees, attractive flora, and fewer floods, and addressing federal Clean
Water Act mandates to reduce pollution of surface waters. These are good
goals. They may complement or compete with one another.

Goals, perspectives and priorities differ.

• LIDs can be attractive “mini-parks” (if we employ people to
  maintain them) and should not be judged solely by how much they
  contribute to meeting one or another federal legal mandate.⁸
• Agency priorities will differ.

DC Water is trying to get U.S. EPA to support re-opening a court order
to give time for rigorous exploration of green technologies as
alternatives to some deep, costly storage tunnels. DC Water wants a few
years to try out a variety of projects on a very large scale — projects
that capture rainwater for human use as well as LIDs.

• DC Water points to Philadelphia’s Green City, Clean Waters
  plan — to test and install many green infrastructure measures that
  could capture pollutants. Philadelphia would thereby side-step
  building storage tunnel structures.
• EPA’s regional regulators (based, ironically, in Philadelphia) are
  resisting DC Water.

To convince EPA, DC Water will want to show that DDOT would permit DC
Water green projects to be built on and under sidewalks — for one
example — even though they compete with other uses of that DDOT-managed
public space, including uses for DDOT LIDs. DC Water focuses its
proposals for intensive “exploration” — or trials — on less than
10 percent of the total land in the District — 20 percent of DC’s
impervious area.

DDOE wants to comply with a new EPA discharge permit which requires
some LIDs, such as planting trees or enlarging tree boxes. DDOE focuses
on two-thirds of the total land in the District but only half of the
impervious area. DDOE measures attack pollutants carried by “first
flush” of rainwater.

DDOT, including its Urban Forestry Administration, focuses on
streetscape, particularly as it comes time to repave streets. Its pace and
priorities are geared to funding limitations, not DC Water’s struggle
with EPA inflexibility.

DDOT’s green infrastructure initiatives face daunting costs and
challenges.

DDOT reports higher costs for LIDs as compared with traditional paving.⁹
I wonder: How much higher seems justified to DDOT? Does the answer turn on
funding source? Can DDOT get costs down? What can we learn from other
jurisdictions? (Montgomery County, MD, has saved time and money by
coordinating DOT and DEP efforts.) Early efforts require site-specific
designs for each greening project. As DDOT (and others) gain experience,
will standardized design templates be feasible for parts of each project?

How can DDOT leverage the private sector to bear costs for more
projects, without public funds? Developers of properties sometimes install
— and commit to maintain — green infrastructure in adjacent public
space. They may look, in return, for clarity of DDOT regulatory policies
and predictability and timeliness of their implementation.

DC Water’s green development technologies proposal needs DDOT help

DC Water seeks to re-open a judicial consent decree for two of the
areas of the City with combined sewers designed to handle both sanitary
sewage and rainwater ("CSO areas") to allow for large-scale
exploration of green development technologies as an alternative (or
complement) to storage tunnel systems for CSO areas in the Potomac River
and Rock Creek watersheds (but not in the Anacostia River watershed). DC
Water priorities and timetables differ from current pace and locations of
DDOT (and DDOE) work.

Much more of CSO areas is impervious than of MS4 areas

DC Water’s “large-scale exploration” would concentrate on two CSO
areas, some 3300 impervious acres out of a total 17,100 acres. See
comparison of impervious acreage in CSO areas and MS4 areas of the City,
by watershed, footnoted below.¹⁰

Executive Branch coordination is essential.

The Executive Branch must coordinate its components, DDOT, DDOE, and DC
Water — as well as DCRA and the Office of Planning — to avoid working
at cross purposes, even unwittingly. Whether DC Water succeeds in
re-opening its consent decree or not, it is vital to assure that pertinent
Executive Branch components intensively coordinate their efforts and
priorities. Coordination demands respect for what each part of the
Executive Branch tries to accomplish and an understanding of how to
determine success.

Well-designed pilot projects are the first order of the day for DDOT,
DDOE, and DC Water — as project sponsors who also regulate one another’s
projects. Intensive coordination is essential,

“MS4 areas” have separate sewers for rainwater and sanitary sewage.
“CSO areas” do not with all Executive Branch components, DDOT, DDOE,
DC Water, and the others asked to take a seat at the table. seat at the
table.

Transparency as to costs of green infrastructure programs

Transparency can help us understand better and make better choices,
getting us the benefits of DDOT insights and expertise. DDOT offers a
model in its web posting as to 33 projects using ARRA funds. DC Water
offers a model in distinctly accounting and billing customers for costs of
its Clean Rivers CSO Long-Term Control Plan — its costliest
EPA-compliance program. It would be constructive for DDOT to formulate its
thoughts about compliance costs due to runoff from DDOT’s impervious
areas.¹¹

Conclusion and recommendation

The District should fully engage DDOT’s, DDOE’s, and DC Water’s
creative enthusiasm and professionalism so as to achieve common benefits
for all.

End notes

1. David Bardin served on DC Water’s Board of
Directors from 2001-2011. This paper derives from his testimony and
six-page submittal to the DC Council, Committee on Environment, Public
Works, and Transportation (“the Committee”) for its March 2, 2012,
Annual DDOT oversight hearing.

2. Total DC impervious surface area — 17,136.9 acres
— analyzed:

Data source: DC OCTO web site

3. Comprehensive Stormwater Management Enhancement
Amendment of 2008. D.C. Law 17-371, effective March 25, 2009, §2(b), DC
Official Code § 8-152.04. Stormwater management and Low Impact
Development grants. Subsection (c) provides:

"(c) Within one year of the effective date of this section, the
Director of the Department of Transportation ("DDOT") shall
submit to the Director [of DDOE] an action plan recommending policies
and measures to reduce impervious surfaces and promote LID projects in
the public space. The action plan shall incorporate:

"(1) New DDOT policies to reduce impervious surface and employ
other LID measures in right-of-wayconstruction projects and retrofit
projects;

"(2) A revised DDOT public space permitting process and the
development of a mechanism to minimize stormwater runoff from the
public right-of-way;

"(3) Requirements and incentives for private developers to
reduce impervious surface and employ LID measures when their projects
extend into the public right-of-way;

"(4) Policies, including fees, for the use of public space to
manage stormwater runoff from private property;

"(5) Policies to address ongoing maintenance of LID or
stormwater best management practices installed in public right-ofway
areas adjacent to private property;

"(6) Strategies to remove impediments to LID projects on
residential properties relating to public space; and

"(7) Costs for each recommendation and a recommended timeline
for funding in the Mayor’s proposed budget. The Mayor shall
incorporate these recommendations in the next and subsequent proposed
annual budgets.

4. The DC law defines “Low Impact Development” as
“stormwater management practices that mimic site hydrology under natural
conditions, by using design techniques in construction and development
that store, infiltrate, evaporate, detain, or reuse and recycle runoff.”
DDOT landscapes LIDs.

5. See recent engineering drawings posted at http://tinyurl.com/riversmartchevy
and http://tinyurl.com/riversmartchevy2
by DDOT for measures about to be started and “City to pilot stormwater
project in Chevy Chase; Environment: Grant will fund permeable alleys,
more,” Northwest Current, February 8, 2012, page 1. Measures
include rain gardens in “bumps” extending from sidewalk, as well as
“green alleys,” among others.

6. http://www.scribd.com/ddotdc/d/84005425-DDOT-Low-Impact-Development-Action-Plan-December-29-2010.

Attachment B sets out DDOT’s Complete Streets Policy of October 18,
2010 which cautiously includes “Improvements to the right of way shall
consider environmental enhancements including, but not limited to:
reducing right-of-way storm water run-off, improving water quality,
prioritizing and allocating sustainable tree space and planting areas
(both surface and subsurface), reusing materials and/or using recycled
materials, and promoting energy conservation and efficiency wherever
possible;” (¶I.f.)

7. Impervious Surface Removal posted at http://ddotdish.com/2012/02/17/impervious-surface-removal/

8. Mayor Gray’s Sustainable DC plan, being developed
by DDOE and OP, will include a strong emphasis on using green programs to
grow green businesses and jobs in the District.

9. See thoughtful DDOT answers to the Committee’s
oversight questions §§ 10.3 (Green alley initiative), 10.4 (Stormwater
runoff reduction), 11.1 (Design standards), 11.2 (Green streets and
alleys), 11.3 (Private development in public space), 11.4 (Statutory
changes), posted on DC Council’s web site.

10. DDOT’s preeminent share of all impervious
surface area in the District drives up Clean Water Act remediation costs
that Clean Rivers IACs must cover — sending price signals to others, but
not DDOT.

11. Impervious Areas by Watershed and CSO or MS4 areas

Data source: DC OCTO web site