Mount Barker District Council (the Council) invites Tenders from Tenderers for the construction of Mount Barker Regional Sports Hub & Surrounds Sewer Scheme (“Scheme”).

Purpose

The proposed sewer gravity and rising mains and associated works are required to provide for the collection and disposal of waste water from the Regional Sports Hub (RSH) and surrounding land.

Scope of Works

The pipelines traverse a Greenfields site with the exception of a road crossing for the connection into Council’s existing wastewater system.

The majority of the land is owned by Council with the exception the rear of No 361 Bald Hills Road (Stephenson) where “right of entry” has been granted and an easement to Council is being secured.

The pipeline generally follows Mount Barker Creek and some is within the flood plain. Precautions will be necessary to protect excavated material from washing into the creek during rain events.

The pipe laying may be undertaken by either open excavation or directional boring.Bored pipeline shall be HDPE PN12.5

The works in this Contact generally include:

a) RSH Gravity Main

• 90 mtrs of 150mm diameter pipe from the maintenance shaft on the north side of Mount Barker Creek to the pump station shell (Xylem) at the pump station pad
• Pipe to be 180 HDPE PN 12.5 laid by directional drilling (tree root zones)
• 1 x maintenance shafts approx. 3.0 mtrs deep
• 1 – 3000mm diameter pump station shell (Xylem) approx. 7 mtrs deep

b) Council Gravity Main

• 310 mtrs of 150mm diameter pipe from the pump station shell at the pump station pad to the maintenance hole at the rear of No 361 Bald Hills Road
• Pipe may be either 150mm DWV SN8 PVC or 180 HDPE PN12.5
• 1 – 1200mm diameter maintenance hole approx 3 mtrs deep
• 1 – 1200mm diameter maintenance hole approx 2 mtrs deep
• 1 – 150mm diameter maintenance shaft approx 3 mtrs deep
• 1 – 150mm diameter maintenance shaft approx 2.5 mtrs deep
• 1 – 150mm diameter maintenance shaft junction approx 3 mtrs deep

c) Stephenson Gravity Main

• 80 mtrs 100mm diameter pipe from the Stephenson septic tank to the maintenance hole on the Council gravity main
• Pipe may be either 100mm DWV SN8 or DN110 HDPE PN10
• 5 – 100mm diameter inspection points approx. 1 mtr deep
• 1 – connection to the Stephenson wastewater pipe (by passing septic tank)

d) Creek Crossing

• 2 – creek crossings with concrete encasement around the 2 pipelines

e) Rising Main

• A rising main (DN140 HDPE PN12.5) 900 mtrs long from the pump station pad to an existing maintenance hole on the corner of Scarborough Way and Parkview Drive
• 3 – 50mm air valves
• 3 – scour valves
• 14 – concrete thrust blocks
• 10 – marker posts
• Fixing rising main to the bridge wall under Bald Hills Road
• Connecting pipe into existing manhole

f) Other Works

• Protection of site works
• Erosion and sediment control
• Testing As Constructed Drawings

Information and Works provided by Council

The drawings and other details associated with the Works include:

• Plans & Longitudinal Sections for the proposed pipeline
• Geotechnical Survey along the gravity pipeline

Works undertaken by Council or Others

• Design approval from the Department of Health
• Approval from the NRM Board for water affecting Activities
• Construction of pump station pad
• Construction of pump station