£
<
\
ro
X
^OST/>%
Q
.SB ?
EPA's BEACH Report:
Northern Mariana Islands
2010 Swimming Season
May 2011
Introduction
The BEACH Act of 2000 requires that coastal
and Great Lakes states and territories report
to EPA on beach monitoring and notification
data for their coastal recreation waters. The
BEACH Act defines coastal recreation waters as
the Great Lakes and coastal waters (including
coastal estuaries) that states, territories,
and authorized tribes officially recognize or
designate for swimming, bathing, surfing, or
similar activities in the water.
This fact sheet summarizes beach monitoring
and notification data submitted to EPA by the
territory of the Northern Mariana Islands for
the 2010 swimming season.
Figure 1. Monitored Northern Mariana
Islands.
Saipan
Tinian
Rota
Table 1. Breakdown of monitored and
unmonitored coastal beaches for
2010.
Island
Total
Beaches
Monitored
Not
Monitored
ROTA
9
9
0
SAIPAN
47
47
0
TINIAN
7
7
0
TOTALS
63
63
0

-------
2010 Summary Results
How many beaches had notification actions?
When water quality standards are exceeded at a
particular beach, Northern Mariana Islands requires
beach managers to post an advisory or closure. An
advisory warns people that there is an increased
health risk associated with entering the water and a
closure warns people to completely avoid contact with
the water. All 63 monitored beaches had at least one
advisory issued during the 2010 swimming season.
Figure 2 presents a full breakdown of notification
actions.
What percentage of days were beaches under a
notification action?
In 2010, about four percent of Northern Mariana
Islands' total beach days were under an advisory
(Figure 3).
How do 2010 results compare to previous years?
Table 2 compares 2010 notification action data with
monitored beach data from previous years.
What pollution sources possibly affect investigated
monitored beaches?
Northern Mariana Islands' officials indicate that no
sources of pollution were found at monitored beaches.
For More Information
For general information about beaches:
www.epa.gov/beaches/
Figure 2: Beach notification actions by duration.

450-|

400-

350-

c
300-
o

'¦*->
t \
250-
<
200-
o

6
150-
z


100-

50-

0-
429
"T"
"T"
2	3-7	8-30
Duration of Actions (days)
>30
Figure 3: Beach days with
and without
notification
actions.
Beach days
with an action:
774
(3%)
Beach days
with no action
26,645
(97%)
Table 2. Beach notification actions, 2008-2010.

2008
2009
2010
Number of monitored
beaches
50
73
63
Number of beaches
affected by notification
actions
39
61
63
Percentage of beaches
affected by notification
actions
78%
83%
100%
Percentage of beach
days affected by
notification actions
2%
3%
4%
Figure 4: Percent of investigated monitored beaches
affected by possible pollution sources (63 beaches).
Percent of beaches
0 10 20 30 40 50 60 70 80 90 100
Investigated / no sources found	100
Non-storm related runoff
Storm-related runoff
Agricultural runoff
Boat discharge
Cone, animal feeding operation
Combined sewer overflow
Sanitary sewer overflow
Publicly-owned treatment works
Sewer line leak or break
Septic system leakage
Wildlife
Other (identified) source(s)
Unidentified source(s)
Note: A single beach may
have multiple sources.

-------