Post-Construction

Post-Construction

Activities in this element reduce pollutants that can result from new developments. The Omaha Stormwater Program staff provides outreach and guidance to the development community and other City departments on stormwater quality planning principals and treatment controls.  Chapter 32 of the Omaha Municipal Code sets standards that new developments must meet (see OMC Chapter 32 Article V).

To demonstrate how various green infrastructure and other practices can help meet the post-construction requirements, the City of Omaha’s has built numerous demonstration projects throughout the Papillion Creek and Missouri River watersheds and were done collaboratively with various community schools and organizations.  The goal is to have the public see and experience different types of green infrastructure and how they reduce stormwater pollution and improve and protect water quality. You can visit the Green Infrastructure page to see more details, but some of the demonstration projects include:

  • Under The Sink rain gardens
  • Cole Creek Restoration Project at Orchard Park
  • Saddlebrook Joint Use Facility
  • The Pawnee Wetlands
  • 58th and Maple, Benson’s East Gateway
  • UNO Welcome Center
  • Creighton Prep
  • Florence Streetscape near 30th and Clay
  • Dundee Elementary
  • Omaha Sewer Maintenance Facility

Bioretention Manual for Designers and Contractors

We have developed a very in-depth manual focused on the most commonly utilized green infrastructure practice, bioretention systems.  The manual will walk you through the Omaha environment, how to assess the site, design and sizing, construction, maintenance, and an in-depth planting guide.  Throughout the manual are insights into real-life experiences that will help you as you create a wonderful bioretention system.  The manual is free to download, see link below.

Frequently Asked Questions


Is it possible to get a building permit without PCSMP document submittal?

Yes, if the project disturbs an area that is greater than 5,000 square feet and less than one acre, the owner may request a Hold on the Certificate of Occupancy contingent on providing a complete PCSMP. If the project is greater than one acre, a complete PCSMP is required for closure of the grading permit; as long as there is an approved Stormwater Pollution Prevention Plan (SWPPP) construction can begin before submitting PCSMP documents.

What information is required for PCSMP As-Builts?

As-built information required for a PCSMP should focus on information associated with the design and function of the BMP.  Typical examples include (but aren’t limited to) invert elevations and spot elevations to ensure drainage flows in the design direction; elevations are also necessary to verify volumes for detention and bioretention areas.

When is a Post Construction Stormwater Management Plan (PCSMP) Required?

A PCSMP is required when a project disturbs an area greater than 5,000 square feet.  The exception to this requirement is if the project involves maintenance of a parking area with no change to the hydraulic grade.

I was told I need a PCSMP for my preliminary plat submittal. I don’t even know the layout yet, how do I meet this requirement?

If you are submitting a preliminary plat, you can meet the Preliminary Plat requirement by applying for a PCSMP project number in the Permix System.  You won’t need to submit all the documentation until you are farther along in the design process.

My project will result in more pervious surface area, do I still need to submit a PCSMP?

Yes, projects that reduce the amount of impervious area will likely meet the no adverse impact requirement, but it doesn’t meet the conditions required for water quality treatment.

What removal efficiency should hydrodynamic separators achieve?

The recommended removal efficiency is 80% TSS removal.  Since the City of Omaha does not have a protocol for mean grain size distribution, size the structure based on the 80% removal curves developed by each manufacturer.

Planning Guidance

The City has developed a guidance document to assist in the development and submittal of a post construction stormwater management plan, click the link below.

 

 

LINKS