Title
Consider and take action on a resolution authorizing revisions to the City’s General Design and Construction Standards Manual (Executive Director of Development Services)
Background:
The General Design and Construction Standards Manual (GDCSM) consolidates the large majority of typical standards needed for the development or redevelopment in League City and compiles them into a single location. This manual was first accepted by City Council on September 29, 2011, and was revised on December 12, 2017 and June 12, 2018.
In the past, revisions to the GDCSM were needed due to specific issues that arose within the City. This update performs a wholesale revision to the GDCSM to bring City design and construction standards to meet or exceed industry standards. This update does the following:
• Sections are renumbered to include a new Section 600 for Reclaimed Water Design Standards which establish criteria for non-potable water systems.
• Sections related to General Provisions, General Design Procedures, General Design and Plan Requirements have been updated to reflect current industry standards and League City needs.
• Water Design Standards, Wastewater Design Standards, Roadway Design Standards, and Drainage Design Standards have been updated to reflect current industry standards and applicable regulatory requirements.
• Adds design and construction standards for Water Booster Pump Stations and Sanitary Sewer Lift Stations.
• Implements an approved products list.
• General Construction Detail Updates to reflect approved products and updated construction requirements.
• Creates a separate Construction Standards and Details manual that captures all graphic details and aligns construction standards to today’s standards.
The review team for this update was led by the Engineering Department, but several representatives from the Public Works Department and the Project Management Office were part of the review team. Staff also provided this draft document to select engineers within the development community to review prior to bring it forward to Council. In general there was agreement on all changes with one exception: Machine placed concrete for roadways - this is often referred to as Slip-Formed. There is some concern that requiring slip-form concrete pavement will reduce the number of contractors that can do this type of work which could result in higher costs to the development community for street installation. Staff believes the reasons to require slip-form concrete pavement outweighs the negatives though as the slip-form process allows for tighter dimensional accuracy meaning that the pavement will have a more uniform thickness than by the manual set-ups in use today. The uniformed thickness reduces bumps and sags in the pavement which in turn allows for an improved surface finish which allows for a more uniform drainage flow pattern on the street and improves the overall ride quality of the street. Having a stricter process for high volume roadways resulting in a more uniformed pavement thickness also has the potential to see some long lasting maintenance impacts as well - less callbacks for grinding pavements due to water ponding, reduces the amount of "thin" areas which extends the overall pavement life. When looking at our neighboring cities, the Cities of Houston, Pearland, Friendswood, and Galveston all have some requirements related to the use of slip-form pavement.
While Staff recognizes the impact to the development community, the benefits seems to outweigh the negatives when looking at heavily traveled roadways. Therefore the updated standards do require slip-form concrete pavement for roadways that exceed 10,000 vehicles per day, so in essence if a roadway is on the City's Master Mobility Plan the pavement will be slip-formed. Hand-forming of pavement on residential streets projected to have less than 10,000 vehicles per day will still be allowed.
This update revises every document from the current GDCSM except for the Traffic Section, which Staff anticipates having this standalone section and related construction standards and details before Council in 2026.
Staff recommends approval of this resolution.
Attachments:
1. Proposed Resolution
2. Exhibit A - Design Standard Sections 100 through 800
3. Exhibit B - Construction Standards
4. Exhibit C - Standard Construction Details
5. Standard Product List
6. Brief Summary of Key Changes
FUNDING
{X} NOT APPLICABLE
STRATEGIC PLANNING
{ X } Addresses Strategic Planning Critical Success Factor #1 - Develop & Maintain our Infrastructure