A gap in the market for a cost effective high-capacity stormwater system and an opportunity to expand their product range, prompted Humes Pipeline Systems to look at the development of a smaller, lighter and easier-to-install unit for their customers. Tony Wilson, Sales Representative and Husham Issa, Senior Technical Engineer for Humes, met with the Tauranga City Council to determine the suitability of a new high-capacity stormwater pit for a large stormwater upgrade project in the city from 3rd to 13th Avenue.
“Humes did consult with us early in the piece to see what our views were for the development of high-capacity stormwater system,” says Phil Bourke, Drainage Operations Engineer for the Tauranga City Council. “Aesthetics is very a important requirement, but of course functionality was the most critical in any design Humes produced.”
The answer was to come up with a design that would not only deal with excess flow from high rainfall events and be cost effective - it also had to look good when installed.
“We looked to develop a system that was 100% precast and which was designed in a way that the as-built capacity is equal to the design capacity,” explains Husham. “We also wanted to eliminate all capacity variations due to the various ways the units could be installed.”
After months of design work and consultation, Husham and the Humes Technical Team had developed a prototype to show Council and Beca - Council’s Design Engineers. The new unit captures stormwater through two flat ductile roadside grates and two large back entry inlets under the kerb giving a total capacity of 400Ltr/sec – 600 Ltr/sec.
“We were asked to view a prototype of a new high-capacity stormwater pit at the Humes Tauranga Sales Centre,” said Gerrit Beker, Engineer for Beca. “With all the data supplied by Humes and after viewing the unit on site, we were able to advise the Council that we were happy with the capacity of the unit for its intended use and it was a welcome alternative to existing systems.”
With Beca giving the ‘thumbs up’ on the new system the Council were then in a position to specify the use of the aptly named ‘HUSH Pit’ - Humes Stormwater High-capacity Pit - at a location in the 9 -10th Avenue stormwater upgrade project. The expected design flow was within the capacity of the HUSH Pit making it a feasible solution for the Council.
“The new HUSH Pit designed by Humes is certainly lighter and easier to manage for installation,” says Neil McLaughlin, Project Manager from Higgins Contractors. “It is also considerably cheaper, which is a big plus.”
“Humes did their homework and the HUSH Pit met the requirements we had given them when they first consulted with us - we have now specified its use in several locations,” adds Phil Bourke.
“The HUSH Pit is smaller, lighter and can be installed without heavy lifting equipment,” adds Tony. “This makes choosing the system not only cheaper in dollar terms but cheaper to install. I think we have certainly filled a gap in the market with the HUSH Pit as it ticks all the boxes.”
- The HUSH Pit has a specialised design for New Zealand conditions
- With a total weight of 3550kg it can be handled by a small excavator
- The compact footprint makes installation easier
- There is no deviation of base course, tarseal or services required
- The correct surface angles incorporated into the kerb entry design save time and eliminate the risk of irregularities from hand trowelling
- Complies with NZS4404:2010 and is suitable for HN-HO-72 loadings