H.Y. Engineering was retained as prime consultant to survey, design, manage, tender, and inspect this extensive 293 single-family lot subdivision in the Yorkson neighbourhood of Langley, BC. The on-site design requirements include the full layout and design of multiple roadways, lanes, and cul-de-sacs with curbs, bulges, gutters, sidewalks, cross sections, street lighting, and temporary roads as required. The design of a storm water management system involved using storm water modeling, flow calculations, the design aquatic habitat features, coordination for the design of rain gardens, and the assessment and coordination of existing detention ponds for expansion as required. Water connections from 80th Avenue were designed with calculations to ensure adequate flows. Storm sewer and sanitary sewer plans illustrated the extension of the trunk mains from the intersection of 81A Avenue and 212th Street to the intersection of 80th Avenue and 212th street.

The project further involved significant coordination with the Township of Langley for input and approvals on designs as well as for the preparation of latecomer agreements. Erosion and Sediment Control design was prepared and monitored by H.Y. Engineering as well as construction inspection with reports to the Township of Langley.

This large multi-phased development, situated on Burke Mountain in Coquitlam, presented unique grading and stormwater retention and infiltration challenges due to the steep slope of the mountain. H.Y. Engineering coordinated with the City of Coquitlam Planning and Development Services Departments to obtain a Development Permit for the project, which included the preparation of the site servicing concept. H.Y. Engineering also provided engineering services for detailed design of the servicing and roadworks required for this project, as well as Erosion and Sediment Control (ESC) design and monitoring.

This subdivision included the creation of 9 single family residential lots.  The existing house on the property was retained on one of the new lots and the overall subdivision concept has maintained the half acre (gross) lot size in the neighborhood. In addition, our subdivision design also includes a concept that will interface with future development on the north side of 27th Avenue.

The site servicing included significant road upgrades as well as the construction of a new cul-de-sac bulb. The ultimate site grading was addressed through minimal retaining walls in order to address undeveloped neighboring properties. In addition, the development also required full storm sewer, sanitary sewer, and water main upgrades in order to service the current and future development. Tree preservation was a concern in this area and a significant number of trees were retained with covenants and unique building envelope designs.

The subject site is adjacent to the Sunnyside Acres Urban Forest Park (located on the east side of 144th Street) and also includes a greenbelt area located at the rear of the proposed lots (dedicated to the City as parkland). This greenbelt is in addition to the existing greenbelt that is running east to west and serves as a connection to the Sunnyside Areas Park for wildlife and pedestrian traffic.

This project required close interaction with the neighboring property owners in order to develop a concept that is consistent with the immediate and surrounding areas as well as ensuring proper interface with existing and future development.