Prioritization of Regulated Construction Sites

Should a project involve a disturbance of soil or have the potential to pose a significant threat to urban runoff or storm water, the project will be subject to additional requirements in order to prevent pollutants from being discharged from the site. Every non-exempt regulated construction project must be assigned one of three priorities (high, medium or low) with respect to the threat the site poses to urban runoff and storm water pollution. Based on the assigned priority, the project proponent will be able to determine the Storm Water Pollution Prevention Plan (SWPPP) and Best Management Practice (BMP) requirements for the proposed project.

To determine the prioritization of a project, the following characteristics are reviewed: size; grading time schedule; proximity to environmentally sensitive waterbody; project type; erosion potential; and potential to produce non-storm water or polluted discharges. To help guide you through the project and assist the City in reviewing the project, a Project Urban Runoff Threat Assessment Form must be completed and submitted with the project’s SWPPP. This form is available at the Engineering and Building Counters at City Hall, as well as on-line (click here for the Project Urban Runoff Threat Assessment Form (161 KB)). A short explanation and directions for completing each section of the form are presented below.

Item 1- Project Size
The total amount of disturbed area of a regulated construction project is important in determining what threat a site poses to urban runoff quality. Project sites greater than five acres and directly adjacent to a sensitive waterbody must be considered high priority. You must enter the estimated total disturbed acreage of the regulated construction project.

Item 2- Planned Period of Grading
The time of the year that a project is to be graded has a direct effect on its potential to discharge pollutants. The State Water Resources Control Bard has set the dates between October 1st and April 30th as the “wet season.” Between these dates, the probability that a significant rainfall event will take place is high enough to warrant the requirement that additional physical Best Management Practices be installed on a project in order to ensure that pollutants from the site entering the storm drain system are reduced to the MEP. In the space provided, you must enter “yes” if the grading activities will take place on the project during the wet season, and “no” if grading activities will not be performed during the wet season.

Item 3-Vicinity of the Project to Environmentally Sensitive Areas
Regulated construction project sites that are five acres or more, and directly adjacent to (within 200 feet), or tributary to an environmentally sensitive area (ESA) must be considered High Priority. Due to the sensitive nature of these waterbodies, however, any site five acres or less and meeting this criteria must be considered a medium priority site. Fourteen ESAs within the watersheds of the City of Oceanside have been identified as the following:

• Pacific Ocean
• Pacific Ocean at San Luis Rey River
• Pacific Ocean at Loma Alta Creek
• Pacific Ocean at Buena Vista Creek
• Oceanside Harbor
• Mouth of San Luis Rey River
• Buena Vista Lagoon
• Loma Alta Slough
• Agua Hedionda Lagoon
• San Luis Rey River
• Loma Alta Creek
• Buena Vista Creek
• Pilgrim Creek
• Guajome Lake

Map depicting these ESAs within the city, and the adjacent and tributary areas surrounding each are available at the Engineering Counter at City Hall. In the space provided, you must enter “yes” or “no” as to whether the regulated construction project was found to be adjacent to or tributary to an ESA.

Item 4-Presence of Significant Erodible Slopes
The presence of significant erodible slopes on a project site affects the project’s potential to introduce sediment to the City’s Storm Water Conveyance System. Runoff on the face of the slopes can obtain enough velocity to cause significant erosion and carry large amount of sediment into the storm drain system. Through the use of the table below, you can determine whether slopes considered to be significantly erodible are present on the site.

*Table was adapted from Table 30-1 of the CalTrans Storm Water Quality Handbooks, Construction Contractor’s Guide and Specifications, April 1997.

Slope 1:20 to 1:4 (V:H)            Slope Steeper than 1:4 (V:H)
Anticipated Period of Grading	Height Greater than 6 ft and less than 12 ft	Height Greater or Equal to 12 ft	Height Greater than 4 ft and less than 6 ft	Height Greater than or equal to 6 ft	Overall Project Profile Steeper than 1:20
Wet Season October 1 to April 30	Yes	Yes	Yes	Yes	Yes
Dry Season May 1 to September 30	No	Yes	No	Yes	Yes

In the space provided, you must indicate either “Yes” or “No” as to the presence of significant erodible slopes on the project site.

Item 5- Potential to Produce Significant Non-Storm Water Discharges or Pollutants
In evaluating the priority of a site during construction activities, it is important to consider the types of non-storm water discharges or pollutants that have the potential to be discharged. Examples of activities that may produce non-storm water discharges, or materials that pose a significant threat to introduce pollutants to urban runoff that commonly found on construction sites are as follows:

• Soil amendments (sediments)
• Fertilizers
• Concrete wastes
• Wastewater as a result of dewatering activities
• Construction materials and compounds
• Types of machinery onsite
• Equipment maintenance and fueling
• Sanitary and septic waste facilities

Item 6- Project Type
It is not necessarily the type of project that has a bearing on the potential to degrade water quality during construction, but the impact of the construction activities and the increase in impervious surfaces that is the real factor. In the space provided you must record the amount of impervious surface to be created, and answer “yes” or “no” as to whether the project will create more than 5,000 square feet of impervious surface.

Item 7- Project Specific Prioritization
Using the information recorded in Item 1-6 on this Form, you must evaluate the project’s overall threat to urban runoff quality using the table below. Based on the size of the project recorded in Item 1, you select the appropriate row on the left-hand side of the table. The next step is to evaluate the project by proceeding to the next column containing a priority. If an answer of “yes” was recorded in the corresponding item of the Form, then the project is considered to be the priority listed in that space. If an answer of “no” was recorded in the corresponding item of the form, then the proponent moves to the next column and repeats the process. If an answer of “no” was recorded for all items on the form, pertaining to columns 2 through 5 of the table, then the proponent records the project as the default priority listed in the final column.

In the space provided, you must indicate the assigned priority for the project.

Project Prioritization Matrix
Project Size	Item 2	Item 3	Item 4	Item 5	Item 6	Default Priority
Greater than 50 acres	High	High	High	High	High	Medium
5-50 acres	--	High	High	High	High	Medium
1-5 acres	--	High	Medium	Medium	Medium	Medium
Less than 1 acre	--	Medium	Medium	Medium	Medium	Low

You are required to submit the signed and completed Project Urban Runoff Threat Assessment Form with your SWPPP. The City Engineering Department will review the completed Form and the assigned prioritization. Should the City find the prioritization assigned is not accurate, you will be notified and the project’s SWPPP may need to be revised accordingly.