BackgroundThe Design Standards were first published in 1993 to provide consistent guidance for the minimum design and technical criteria for the construction of public infrastructure. The last revision was adopted by City Council in July of 2007. The current standards include criteria for public streets, storm drainage systems, water systems, sanitary sewer systems, arterial and greenway landscaping and bikeways, and electric infrastructure. These standards are technical in nature and apply to the way in which the improvements are to be constructed and are complimentary to the Land Development Code which includes zoning regulations and guides the overall use and layout design for development.
This update to the Design Standards encompasses all seven chapters due to the time that has transpired from the previous revision. In addition to addressing sustainability, Envision Longmont and Development Code revisions, the major goals for each chapter include:
- Section 100 General Requirements: The changes to this section revolve around clarification of the plan submittal and review process as well as the construction inspection and approval process. This includes clarifications to the exception process. Clarification of utility spacing in public right-of-way and excavation and trenching requirements.
- Section 200 Transportation: This section has changed from Street Construction to Transportation to better represent how this section has encompassed multi-model transportation design standards including bike lanes, sidewalks and trails. The update of accessible ramp configurations as well as updates to conform with recent changes to the CDOT standards is a priority. The alignment and geometry of streets has been updated to reflect the most recent AASHTO recommendations as well as the latest MUTCD standards.
- Section 300 Storm Drainage: The main goal of the revisions of this chapter are to replace the 1984 Storm Drainage Criteria Manual with references to the current methodologies of the Urban Drainage Flood Control District. The approach to calculating rainfall intensities, hydrology, conveyance design and storm water storage have changed significantly. The section will also provide minimum standards for ground water underdrain systems in accordance with the Municipal Code.
- Section 400 Wastewater Collection: The overall capacity calculation methodology will be changed to reflect the master planning completed over the last few years. Actual meter data will be used to determine average daily flow for designing new systems and evaluating existing capacity.
- Section 500 Water Distribution: The material and construction requirements shall be modified to reflect changes in the American Water Works Association (AWWA) standards and general construction practices. Water meter sizing and backflow requirements will be included to reflect recent State regulations.
- Section 600 Landscaping and Irrigation: The changes to this section are intended to reflect current best practices including water conservation efforts as well as bringing uniformity to systems operated and maintained by the Operations Group within Natural Resources. There have been modifications to clarify use of raw water irrigation and general construction practices. Large structures that were covered in the previous standards have been relocated to Section 200 Transportation to aid in readability and compatibility through the standards. Extensive work has been done to update the approved materials list to allow greater number of native species and address operational needs.
- Section 700 Longmont Power and Communications: Modifications will address current design and construction standards as well as provide guidance for small cell facilities. The language also includes new standards for metering.
The draft Standards provided here have been compiled by review committees made up of staff from across Public Works and Natural Resources. A committee for each section was comprised of a coordinating engineer, a senior engineer in the discipline, a construction inspector and an operations supervisor.
The draft is being reviewed by a third party for conformance with best practices and uniformity. These comments will be incorporated prior to going to City Council for approval.
The draft will be presented to the Transportation Advisory Board, Parks and Recreation Advisory Board and the Sustainability Advisory Board for comment. These comments will be incorporated prior to being presented to City Council for approval.
Drafts will be updated periodically as they are revised due to the number of entities providing comments. Check this website for updates.
Public comment is being sought through this website. We encourage the public to download the sections of interest and provide comments to us through August 9, 2019. At the close of the comment period, staff will evaluate comments and present the final document to City Council for approval and adoption through an ordinance.
For questions about this project, contact Public Works at 303-651-8330 or by email at PWEng@longmontcolorado.gov