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Developers
In July, 2013, the Central Coast Water Board adopted Order R3-2013-0032, with new, more stringent Post-Construction Requirements (PCRs). Projects that receive their first discretionary approval for design elements after March 6, 2014 — or, if no discretionary approval is required, receive their first ministerial permit after that date — are subject to the PCRs, if they create or replace 2,500 square feet or more of impervious area. 

Stormwater Technical Guide

Applicants for development approvals in jurisdictions within the Monterey Regional Stormwater Management Program should use the Stormwater Technical Guide when preparing Stormwater Control Plans. However, local requirements vary. Check with staff in the jurisdiction where your project is located to identify differences that may apply. A pre-application meeting is recommended for all projects subject to the PCRs.

  • Presentation slides regarding the Stormwater Technical Guide are available here (PDF). A recording of a similar presentation that occurred in Santa Maria, CA, is available here (video; 3hrs 9min).

Requirements at a Glance*

Type of Project Performance Requirements
Tier 1

Projects, including single family homes that are not part of a   larger plan of development (SFHs), that create or replace 2,500 square feet or more of impervious surface.
Implement LID Measures:

Limit disturbance of natural drainage features.

Limit clearing, grading, and soil compaction.

Minimize impervious surfaces.

Minimize runoff by dispersing runoff to landscape or using permeable pavements
Tier 2

Projects, other than SFHs, that create or replace 5,000 SF or more net impervious surface**.

SFHs that create or replace 15,000 SF or more net impervious surface.

Tier 1 requirements, plus:

Treat runoff with an approved and appropriately sized LID treatment system prior to discharge from the site.
Tier 3

Projects, other than SFHs, that create or replace 15,000 SF or more of impervious surface.

SFHs that create or replace 15,000 SF or more net impervious surface.
Tier 2 requirements, plus:

Prevent offsite discharge from events up to the 95th percentile rainfall event using Stormwater Control Measures
Tier 4

Projects that create or replace 22,500 SF of impervious surface.
Tier 3 requirements, plus:

Control peak flows to not exceed pre-project flows for the 2-year through 10-year events

* These thresholds, along with a project's Watershed Management Zone (WMZ) designation, determine the specific requirements applicable for project determination.

** Net impervious surface equals new and replaced impervious area minus the total pre-project-to-post-project reduction in impervious area (if any).

Additional Resources

Environmental Protection Agency's (EPA) Low Impact Development (LID) web page

Regional Water Quality Control Board Post-Construction Stormwater Requirements

Regional Water Quality Control Board Low Impact Development web page

California Stormwater Quality Association (CASQA) California LID Portal

Central Coast Low Impact Development Initiative Technical Guidance web page

Education and Training
Please Keep Motor Oil,Soap, and Paint Out of the Streets and Storm Drains

Copright © 2012 Monterey Regional Stormwater Management Program. All Rights Reserved.

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