[Ord. No. 2695, Added, 2-16-2016]
An application shall be made on such forms and contain such information as the City Manager may require. If a railroad-highway crossing provides or will provide the only access to land that is the subject of the application, the applicant shall indicate that fact in the application.
[Ord. No. 2695, Added, 2-16-2016; Amended, 11-19-2024 by Ord. No. 2948]
1. 
The City Manager shall administer this Code and may furnish additional policy, criteria and information including specifications and procedures for the proper implementation of the requirements of this Code. The documents containing stormwater requirements include the Lake Oswego Stormwater Management Manual (SWMM), the Engineering Design Standards, and the Standard Detail Drawings. In the event of a discrepancy between the documents, the requirement that is most protective of water quality will apply.
2. 
The City Manager is delegated authority to adopt, revise, and update the Stormwater Management Documents as necessary based on:
a. 
The latest federal and state stormwater or water-quality requirements; or
b. 
Improvements in current industry practices.
[Ord. No. 2695, Added, 2-16-2016; Amended, 11-19-2024 by Ord. No. 2948]
1. 
For purposes of determining project class, all projects on a parcel or contiguous parcels under common ownership conducted within a three-year period shall be considered cumulatively.
2. 
Small Projects are those projects that create new impervious area that is greater than or equal to 1,000 square feet but less than 3,000 square feet.
3. 
Large Projects are those projects that that either create new, redevelop (replace), or both create and redevelop, impervious area that is equal to or greater than 3,000 square feet.
4. 
Repair or maintenance activities on structures or facilities with greater than or equal to 3,000 square feet of existing impervious surface are subject to the requirements for large projects in subsection (3), above.
5. 
Projects that are renovations or replacements of existing stormwater facilities shall be classified according to the amount of existing impervious area on the property that is not currently receiving treatment.
[Added, 11-19-2024 by Ord. No. 2948]
1. 
All projects shall use, to the maximum extent practicable, site planning and design technique(s) that reduce post-development runoff rates, volumes, and pollutant loads to match pre-development conditions. Such techniques include, but are not limited to, minimization of impervious surface, use of on-site retention to reduce the volume and rate of runoff entering the stormwater management system, development design that reduces the rate and volume of runoff from impervious surfaces, and distributed stormwater management practices that intercept and treat runoff from developed areas.
2. 
Stormwater shall be managed in as close proximity to the development site as practicable and avoid a negative impact on nearby streams, wetlands, groundwater, and other waterways.
3. 
All projects shall use onsite retention of stormwater to the extent allowed by the site's infiltration capacity, as determined by an infiltration test, and within setbacks designated by the SWMM.
4. 
To the maximum extent practicable, stormwater facilities shall be designed to infiltrate the stormwater runoff created by impervious area at the site during the 10-year, 24-hour storm event. A technical analysis using a site's topography, the results of an infiltration test, and other information required by the City Engineer, shall be submitted to the City Engineer for review if the project cannot infiltrate 100% of the runoff created by the impervious area on the site.
5. 
Off-site discharges shall be to a location approved either:
a. 
Under a development permit issued under LOC Chapter 50; or
b. 
For projects not requiring a development permit, as a part of the City Engineer's construction plan review.
6. 
All local, state, and federal permit requirements related to implementation of stormwater management facilities must be met prior to approval of the City's final inspection of the stormwater facility.
7. 
Underground Injection Control (UIC) facilities must be reviewed and approved by DEQ unless rule-authorized pursuant to OAR 340-044-0018. Stormwater shall not be discharged to a UIC that does not meet DEQ requirements.
8. 
Stormwater System Design.
a. 
Applicants shall submit a stormwater report that quantifies and describes all impervious areas on the site and the treatment methods used to meet the requirements of the SWMM.
b. 
The applicant's designer shall be responsible for all stormwater system design, Stormwater Report, and Operations and Maintenance Plan.
c. 
Stormwater reports must address all criteria required by the Stormwater Management Documents. Incomplete reports will be returned to the applicant.
d. 
Any modification of a stormwater report or the construction of a City-approved stormwater system, public or private, shall be submitted to the City Manager for review and approval.
e. 
Operations and Maintenance (O&M) Plan.
i. 
The Operations and Maintenance Plan shall list the responsible party(s) of the stormwater facility.
ii. 
An O&M Plan must be prepared for private and public stormwater facilities, submitted to the City Manager for review and approval, and recorded in the county in which the property/facility is located.
iii. 
The O&M Plan shall contain any agreements regarding operations and maintenance of stormwater facilities that are required as a condition of approval.
[Ord. No. 2695, Added, 2-16-2016; Amended, 11-19-2024 by Ord. No. 2948]
1. 
The applicant shall obtain a Public Improvement Permit for public stormwater infrastructure.
2. 
Notices.
a. 
Prior to project mobilization, the applicant or applicant's agent shall schedule and attend a pre-construction meeting with the City Engineer.
b. 
The applicant or applicant's agent shall notify the City Engineer and the applicant's design engineer 48 hours prior to starting construction work on the public. The City shall either provide written authorization to proceed or provide an Engineering Construction Inspector to monitor the construction. The applicant's design engineer or designee must be present during the construction of stormwater facilities and photo-document the process.
3. 
Certificate of Acceptance.
a. 
A Certificate of Acceptance will be issued after construction is complete and the warranty period has been successfully completed.
b. 
The City Engineer shall periodically inspect public stormwater facilities that have not been issued a Certificate of Acceptance. Inspections shall document required maintenance and note any discrepancies from the O&M Plan and the City-approved stormwater design.
c. 
A final inspection and approval by the Engineering Dept. is required before a Certificate of Acceptance is issued and the construction security required under LOC § 50.07.003.9.a is released for the project.
[Ord. No. 2695, Added, 2-16-2016; Ord. No. 2890, Amended, 3-17-2022; Amended, 11-19-2024 by Ord. No. 2948]
1. 
The responsible party shall:
a. 
Inspect and repair stormwater facilities to maintain their design capacity and treatment capability;
b. 
Clean conveyance structures and catch basins as necessary to maintain their design capacity.
c. 
Maintain access lanes and pathways to stormwater facilities.
2. 
Repairs and Maintenance.
a. 
All repairs and maintenance shall be in accordance with the SWMM and, if issued, the Operations and Maintenance Plan (O&M Plan). If an O&M Plan was not issued, the maintenance of the stormwater facility shall comply with current industry practices.
b. 
The City may require the applicant to conduct more frequent inspections and/or maintenance when necessary for its proper function at the design capacity.
c. 
Failing or Failed Stormwater Facilities.
i. 
Stormwater facility renovations, restoration, or replacements shall be submitted to the Engineering Department for review and approval. Submittals shall include all information required by the current Lake Oswego Stormwater Management Manual.
ii. 
Stormwater facility restorations must bring the failing stormwater facility into compliance with the original approved plans or land use requirements. The land use requirements will prevail if a conflict exists between the approved plans and the land use requirements.
iii. 
Stormwater facility renovations must bring the failing or failed stormwater facility into compliance with the requirements of the current Lake Oswego Stormwater Management Manual.
iv. 
Stormwater replacements must conform with the requirements of the current Lake Oswego Stormwater Management Manual.
d. 
City Inspections.
i. 
All public and private stormwater facilities shall be reasonably accessible for City inspections. The responsible party shall ensure inspection access for public facilities through an easement to the City. (See LOC § 38.25.160(1) for easement requirements.)
ii. 
The City Engineer shall establish inspection programs to evaluate and enforce compliance with the requirements of this article, which may include but are not limited to, routine inspections, random inspections, inspections based upon complaints or other notice of possible violations, or joint inspections with other agencies inspecting under environmental or safety laws.
e. 
The responsible party shall:
i. 
Document all records of maintenance activities and facility repair as described in the Operations and Maintenance Plan.
ii. 
Retain the maintenance records for a minimum of ten years.
iii. 
Transfer the records to the successor responsible party of the stormwater facility.
iv. 
Provide duplicate copies of the retained records to the City Engineer upon request and at reasonable times. The records may be retained by electronic methods.
f. 
The applicant and successor Responsible Parties shall inform purchasers and other successors and assignees of the property of the existence of private stormwater facilities on the site and the requirements for inspection and maintenance.
3. 
In the event the City Manager has reason to believe that a stormwater facility has not been maintained in a manner that retains its design capacity or treatment capability or that it has become a threat to public safety, health and welfare, or to water-quality requirements issued by DEQ to the City:
a. 
The City Manager shall notify the responsible party by certified mail at the address shown on the most recent tax assessment roll. If the responsible party is an entity, notice may also be given to an officer of the entity or to its registered agent as shown by the records of the Secretary of State.
b. 
The notice shall specify the failed or failing components of the stormwater facility and the measures needed to comply with the design.
i. 
The notice shall specify a correction period.
ii. 
For structural repairs, the responsible party must submit a proposed plan within the correction period to the City Engineer for review and approval. The proposed plan must include a schedule for completing the required repairs.
c. 
If corrective measures are not completed within the correction period or the correction plan's timeline, then the City Manager may pursue enforcement procedures pursuant to this Article, or otherwise allowed under the Lake Oswego Code.
[Added, 11-19-2024 by Ord. No. 2948]
1. 
Exemptions.
a. 
Projects undertaken during an emergency, such as where there is immediate danger of landslide, damage to public or private property, or failure of a public facility.
b. 
Re-development in response to a natural disaster or fire when the re-development does not expand beyond areas that were managed previously in conformance with LOC § 38.25.125.
c. 
Utilities.
i. 
Maintenance, repair, or installation of utility facilities, e.g. pipes, conduits, and vaults, that include replacing the ground surface with in-kind material or materials with similar impervious characteristics.
ii. 
Utility work where only trenching is done and where the new surface has the same impervious characteristics as the original surface.
d. 
Pavement Maintenance.
i. 
Pothole repair, crack sealing, and square cut patching.
ii. 
Pavement overlays that do not expand the area of coverage.
iii. 
Slurry seal.
iv. 
Pavement maintenance that does not extend below the top of the road base.
2. 
Variances.
a. 
Variance Application Requirements.
i. 
An application for a variance must be submitted in writing to the City Engineer and must:
A. 
Describe the project including the location and purpose;
B. 
Identify the specific requirement in the Code or Stormwater Management Documents for which the applicant is applying for a variance;
C. 
Submit a stamped engineering analysis demonstrating that the criteria of subsection (b) is met; and
D. 
Propose mitigation measures to compensate for the variance, including a stamped engineering analysis and modeling showing how the project will not reduce water quality or cause hydromodification.
ii. 
The applicant shall submit complete and accurate information; incomplete or inaccurate submittals will be returned to the applicant for re-submittal.
iii. 
Additional material supporting the need for a variance may be required by the City Engineer.
iv. 
The applicant shall include a fee with the application as set by resolution of the Council from time to time.
b. 
Approvals.
i. 
The City Engineer may approve a variance:
A. 
When the variance, as mitigated, will not increase risks to public health, safety, and welfare, or to water quality or quantity, or to public and private property as determined in a Downstream Analysis (see SWMM for details); or
B. 
Where the requirement:
(1) 
Will cause harm or a significant threat of harm to public health, safety, and welfare, including water quality or quantity, or harm public and private property; or
(2) 
Is not technically feasible.
C. 
Only to the extent necessary to alleviate the condition;
ii. 
Approval is limited to the specific variance granted for the specific project.
iii. 
The City Engineer shall provide a written decision that approves or denies the application, and summarizes the findings regarding the criteria. The City Engineer may impose conditions of approval if needed to meet the criteria. The City Engineer's decision is the final decision of the City.
c. 
The variance submittal and documents approving or denying the variance will be retained with the Engineering Department's project documents.