Stormwater Pollution Prevention Plan - Phoenix Sky Harbor ...

separate storm sewer system (MS4) and some drain airport property only. The Salt River
(located along the airport’s southern boundary) is the receiving water system for
stormwater discharges from PHX. The Salt River is a dry riverbed during most of the
year except during periods of water release from the Granite Reef Dam, located
upstream, and during storm runoff events. PHX has approximately 20 feet of relief
between the western and eastern boundaries of the airport, with a gradient of 8 feet per
mile sloping to the west. Drainage basins connected to an extensive underground
drainage system primarily collect surface runoff. The Salt River is not considered an
impaired water on the 2006/2008 303(d) Impaired Waters List or an outstanding Arizona
water (OAW) under A.A.C. R18-11-112.
3.3 Site Map
Figure 3 depict the locations of drainage patterns, drainage basins, outfalls and receiving
waters. Figures 2, 3, 4 and 5 present the data required in MSGP-2010 Parts 5.1.2.3 and
6.S.5.2, which are:
• Size of the property in acres
• Location and extent of significant structures and impervious surface
• Directions of stormwater flow
• Locations of stormwater conveyances (e.g., ditches, pipes and swales)
• Locations of the existing structural control measures
• Locations of surface water receiving the facility’s discharges or impaired waters or
OAWs within 2.5 miles downstream of the facility
• Locations of discharges to a regulated MS4
• Locations of potential pollutant sources identified under MSGP-2010 Part 5.1.3.2
• Locations where significant spills have been identified or leaks have occurred under
MSGP-2010 Part 5.1.3.3
• Locations of stormwater monitoring points
• Locations of stormwater outfalls, each with unique identification codes, indicating the
outfalls authorized as “substantially identical” under MSGP-2010 Parts 4.2.3. and
5.1.5.2 and an approximate outline of the area draining each outfall
• Locations of activities that are exposed to stormwater with potential discharge from
the facility
There are co-permittees at PHX subject to MSGP-2010 requirements that are not
included in Figures 1 and 2. These entities provide on-site services without having a
leasehold location at the airport and include wash service providers. While they conduct
Sector S specific industrial activities at PHX, the place of business is located off site.
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