San Diego Water Authority leads charge to establish TMDLs for bacteria-impacted waters
- By John H. Reaves
- Jul 01, 2007
The San Diego Regional Water Quality
Control Board, in one of its
most ambitious programs to date,
proposes to set up rules that will
reduce bacteria in stormwater
runoff that flows to the coastline. In the past,
the board has targeted chemicals. Now it is
proposing to tackle bacteria, which originate
in the intestines of warm-blooded animals
(such as birds, feral cats, pets, livestock, horses,
and humans) and have chronically exceeded
safe levels. Pollution warnings have been
Fecal bacteria have long been measured as
an indicator of human pathogens in water.
Those pathogens threaten the health of recreational
users and those who eat shellfish. The
board has made bacteria reduction a priority
due to the human health concern and the
potential economic losses associated with beach
closures. There are huge challenges to identifying
and controlling the myriad natural nonpoint
sources of bacteria in the watershed,
including the cost to cities and counties that
must implement the board’s ultimate order.
In 2003, the Regional Water Quality Control
Board for the Los Angeles region (Long
Beach to Ventura) adopted a basin plan
amendment that established total maximum
daily loads (TMDLs) for bacteria after obtaining
state and federal approval. All regions within
its jurisdiction are covered during “wet
weather,” whereas certain “reference” areas,
including Santa Monica Bay beaches, were
identified for “dry weather” while more information
is gathered from other areas. It is still
too early, according to one staff member
knowledgeable about the local process at the
San Diego board, to comment on its effectiveness
Southern California is not the only region
facing these issues. Other regions across California,
such as Tomales Bay and Napa River,
and all across the country, including parts of
the lower Mississippi and Chesapeake Bay, have
recently approved TMDLs for bacteria or are
in the process of doing so.
The legal authority for the bacteria order
starts with Section 303(d)(1)(A) of the Clean
Water Act, which states, “Each state shall identify
those waters within its boundaries for
which the effluent limitations … are not stringent
enough to implement any water quality
standard applicable to such waters.” The board
must develop TMDLs to restore such waters.
The board defines TMDLs as “the sum of
the individual waste load allocations for point
sources and load allocations for nonpoint
sources and natural background such that
the capacity of the waterbody to assimilate pollutant
loading (the loading capacity) is not
exceeded.” In other words, the board divides
and allocates the maximum pollutant standard
among all the contributing sources.
The San Diego board first proposed in 2003
to address 19 of the 38 bacteria-impaired
waterbodies with new TMDLs, from San
Diego to southern Orange County. The board
identified those waterbodies in its 2002 List of
Water Quality Limited Segments, updated
in 2006, which was compiled pursuant to Section
303(d). After drafting a technical report,
seeking public input, and a series of revisions,
the board on April 25 held a public hearing on
the proposed basin amendment to include
numeric targets in the TMDLs for bacteria. A
follow-up hearing was planned for June 13. A
final decision will not likely occur until this
fall, and that will be subject to state and federal
There are 12 different watersheds that contribute
runoff to the coastline subject to the
proposed TMDLs, each with unique attributes
and sources. Twenty-six cities, Orange
and San Diego counties, Caltrans, flood control
districts, and owners/operators of
stormwater drains will be swept up by these
new TMDLs. The magnitude and complexity
of the issues is staggering.
Specifically, the board is seeking to amend
its basin plan, pursuant to California’s Porter-
Cologne Water Quality Act (under Section
13240 of the Water Code), in order to add the
proposed TMDLs. If amended, the plan would
then affect creeks, shorelines, and creeks discharging
to the ocean. The board also must
prepare an environmental impact report under
the California Environmental Quality Act in
conjunction with the amendment.
Stringent numeric levels are designed to
protect not only human health but also shellfish
harvesting from bacteria.
The board will implement new TMDL
requirements, primarily by inserting them into
National Pollutant Discharge Elimination System
(NPOES) permits for storm drains as
coastal communities seek permit renewal.
Storm drains are treated as point sources, yet
they are hardly like point sources in the historical
sense, such as an industrial discharge
from a facility. Nearly all upstream nonpoint
sources merely funnel runoff through such
drains at the end point, making them a practical
target of regulators.
NPDES permitees will be required to develop
bacteria load reduction plans, use “best
management practices,” and implement monitoring
components to achieve those goals.
The board also considers the Porter-Cologne Water Quality Act to be its principal
source of authority to regulate nonpoint sources with TMDLs. “Management measures”
will be used to reduce nonpoint loads.
No uniform runoff
In preparing TMDLs, the board used models
that took into account episodic storms in which
high levels of bacteria enter the coastline as well
as “dry-weather urban” runoff, given San
Diego’s limited rainy season. Wet-weather flows
are defined as 0.2 inches of rain or more in any
72-hour period. Dry-weather flows include all
other times; these often are caused by excess
irrigation and by washing cars and hardscapes.
The runoff is not uniform. Moreover, a portion
of urban runoff that does not enter a storm
drain comes from “uncontrollable” sources,
such as birds and wildlife. The board claims it
will focus on controllable sources. The TMDLs,
however, must be met regardless of the source.
There are concerns among the cities and counties
that the net effect is to have a “zero” discharge
policy from all non-natural sources.
The board has not yet decided whether it will
allow a certain number of days of exceedances,
as allowed by Los Angeles. Because rainy days
cause an uncontrollable deluge of bacteria and
contaminant-laden runoff to surge through storm
drains to the coastline, exceedances are inevitable
given today’s storm drain configuration.
There is a certain leap of faith in the board’s
approach. The board openly states limitations
may change over time as better scientific understanding
of the interplay of bacteria and human
health evolves. For instance, the board acknowledges
that spikes in bacteria associated with
urban runoff do not necessarily correlate with
increased human pathogens, citing local studies
done in 2003 and 2004. In one example,
bacteria “regrows” and peaks at low tides in
eel grass and likely does the same in storm drains
during tidal fluctuations. As can be imagined,
that regrowth phenomenon is one of the significant
challenges cities will face. The regrowth
then competes, along with bird and other animal
wastes, with bacteria loads from other
sources. It also is not clear whether birds, which
do not come in contact with humans, carry
More studies are needed to
better correlate bacteria with pathogens.
As noted by Mo. Lahsaie, the Clean Water
Program coordinator for Oceanside, Calif.,
cities must identify the sources of bacteria, both
anthropogenic and natural, in the watershed
affecting their jurisdiction. Oceanside is under
the jurisdiction of the San Diego board.
typically compete for limited grants to help
fund their investigation. After identifying the
sources, Lahsaie states their task will be to eliminate
them. Residential and agricultural sources
are particularly difficult to control, he said. Of
course, there will be an educational component
to make residents aware of the issues, leading,
perhaps, to enforcement and penalties for
noncompliance. That is virtually inevitable
as communities will face threats of citizens’
suits for violating their NPDES permits.
Some cities are diverting or considering how
to divert dry water flows before they enter
creeks and rivers. Others, like the city of
Oceanside, may have to install more ultraviolet
light or ozone treatments at the mouths
of creeks and rivers. In the end, if the communities
are unsuccessful at meeting the
TMDL requirements upstream of the storm
drains, they will have to address them by diverting
runoff from the storm drain to sanitary
sewers. The capital expense to install piping
and expand sanitation facilities will be, well,
incapacitating in many instances.
Compliance must occur within 10 to 17
years, depending on location. Differences
depend on, for example, amount of swimmer
use, whether shellfish are harvested or not, and
frequency of exceedances for a particular area.
NPDES permittees have a formidable task
ahead, not only in terms of finding technical
ways to comply with the TMDLs but finding
the money to do so. How much will it cost?
The estimated upper range by larger permittees
goes up into the billions. Whether that
proves to be the case remains to be seen. The
imposition of the bacteria TMDLs in San
Diego will not be immediate, with the measures
that will be used still in formulation.
Next in line are TMDLs for San Diego Bay
and Dana Point Harbor. The board has ordered
coastal communities to investigate the impact of
bacteria, nutrient, and sediment loads to lagoons
and provide necessary data for the board to then
formulate TMDLs. You can be sure the cities
and counties will relish picking their poison.
The link to the San Diego board’s Web
site regarding this issue is http://www.waterboards.
This article originally appeared in the 07/01/2007 issue of Environmental Protection.
John H. Reaves, who practices environmental law from San Diego, received his J.D. from Santa Clara University School of Law in 1983. His practice emphasizes all hazardous and solid waste matters. He has lectured frequently on environmental and insurance matters and has co-chaired the Environmental Law/Land Use Section of the San Diego County Bar Association for most of the years since 1986.