Stormwater Construction General Permit (CGP)
To learn more about Construction General Permit visit our new website at http://www.azdeq.gov/cgp.
Related 2013 CGP Documents
Stormwater discharges generated during construction activities can cause an array of physical, chemical and biological water quality impacts. Water quality impairment results, in part, because a number of pollutants are preferentially absorbed onto mineral or organic particles found in fine sediment. The interconnected process of erosion (detachment of the soil particles), sediment transport and delivery is the primary pathway for introducing key pollutants such as nutrients (particularly phosphorus), metals, and organic compounds into aquatic systems.
Stormwater runoff from construction sites can include pollutants other than sediment such as phosphorous and nitrogen, pesticides, petroleum derivatives, construction chemicals and solid wastes that may become mobilized when land surfaces are disturbed.
The Construction General Permit (CGP) covers stormwater discharges from construction activities in Arizona, except for those construction discharges in Indian Country.
There is a waiver option for small construction activities provided in the stormwater Construction General Permit (CGP). To be eligible for this waiver option the operator must meet the following criteria:
- The project must disturb less than 5 acres;
- The project cannot be located within 0.25 miles of an impaired or outstanding Arizona water; and
- The project must have an "R" (or erosivity) value of less than 5. Additionally, ADOT projects are not eligible for the waiver option.
Additional information about the construction rainfall erosivity waiver can be found under "Additional Resources", below.
Construction General Permit (CGP)
CGP authorizes stormwater discharges from construction-related activities where those discharges have a potential to enter surface waters of the United States or a storm drain system. Note the Arizona Pollutant Discharge Elimination System (AZPDES) authorizing statute uses the term navigable waters, which is defined as equivalent to the waters of the United States. However, because the term navigable waters can be confusing to the general public (i.e., the definition of navigable waters also includes ephemeral washes, intermittent streams, playas, and wetlands, that may not be able to be traveled by conventional vessels), this permit generally references discharges to waters of the United States.
To obtain authorization for discharges of stormwater associated with construction activity, the operator must comply with all the requirements of the general permit and submit a Notice of Intent (NOI) in accordance with Part 2.3 of the general permit.
- NOI Construction Database Search
For helpful information on developing Construction Stormwater Pollution Prevention Plans (SWPPP), including templates and instructions, please see "Additional Resources", below.
The SWPPP must be on-site whenever construction activities are actively underway and must be fully implemented and maintained as construction activities progress.
If ADEQ does not issue the authorization certificate within seven days, or 30 calendar days for sites located within 1/4 mile of an impaired or outstanding Arizona Water, of receiving the NOI or otherwise notify the operator that the submitted NOI is deficient, the operator may commence construction activities without an authorization certificate; however, it is the operator's responsibility to verify the date the NOI was received by ADEQ before initiating construction activities. Whether or not ADEQ notifies the operator of a deficiency in the NOI, discharges are not authorized under this permit if the operator submits and incomplete or incorrect NOI.
Notice of Termination
Generally, after the construction project is complete and the project's disturbed area is stabilized to at least 70 percent of natural background density or responsibility for the project has been assumed by another operator, the permittee must submit an NOT (See part 2.5 of the permit for specific requirements.)