Enquiries about the contents of this document should be directed to:
Dylan Strong, CEO, District Council of Orroroo Carrieton
Phone: (08) 8658 1260
Email: council@orroroo.sa.gov.au
OR
Stuart Shute, Works Coordinator, District Council of Orroroo Carrieton
Phone: 0498 067 733
Email: stuart.shute@orroroo.sa.gov.au
Expression of Interest due Friday 3rd December 2021
Submissions to Margaret.chapman@orroroo.sa.gov.au

WILMINGTON CARRIETON ROAD CULVERT (500 m from Town)

There are two options for this site.
Option “A” is to remove the culvert entirely and replace it by a sealed floodway.
Option “B” is for extensive repairs to the existing infrastructure

Scope Option “A”: Removal of Culvert. Replacement by Sealed Floodway

5.1.A.1 Remove debris from waterway both upstream and downstream.
5.1.A.2 Cut damaged apron and remove concrete and loose debris from waterway down
stream, reshape waterway to leave smooth profile. Allow to roll waterway profile to
the satisfaction of Council.
5.1.A.3 Excavate and remove existing culvert and road embankment to new vertical
profile.** (see note below). Feather out to existing seal 50m in both directions from
the culvert centreline.
5.1.A.4 Construct edge beams each side of the floodway zone 100m long, 500mm x 350mm
reinforced with 6 x 12mm deformed steel bars each.
5.1.A.5 Construct new pavement 10m wide x 100m long, 150mm subbase of PM2 30QG or
as approved by Council from local sources.
Base layer to be 100mm PM2 20QG or as otherwise approved by Council from local
sources.
5.1.A.6 Seal 100m by average 9m width with 14/7 sprayed chip seal.
5.1.A.7 Cart nominal 350m3 loose spoil, surplus rock, removed vegetation, culvert elements
and demolished breakout concrete to approved dump 5km lead.
5.1.A.8 Clean out and reinstate one side swale 3m wide X 15m long. Add rock armour
nominal 50mm- X 125mm thick.
5.1.A.9 Allow one day excavator and roller time to clean out and reinstate approach
channels (2 of).
5.1.A.10 Signs and edgelines to be by Council.
5.1.A.11 (Re-) fencing to be organised by Council separately.

** Note: Council to organise lowering of Telstra Cable along upstream side of road.

Details to be amended as necessary at Pre-tender Site Meeting.

Scope Option “B”: Repairs to the Existing Infrastructure

5.1.B.1 Cut and remove undermined section of downstream-side wingwall.
5.1.B.2 Stabilise and underpin remaining wingwalls downstream with 32 mpa concrete
25m X 600mm X 600mm.
5.1.B.3 Cut damaged apron and remove concrete and loose debris from waterway down
stream.
5.1.B.4 Reconstruct 32 mpa concrete downstream apron 125mm thick with SL72 mesh
on compacted PM2 base 2m X 10m. Key in trailing edge with roughcast beam
300-500 average. M12 mesh reo in edgebeam.
5.1.B.5 Sawcut seal 40m long, clear each way from damaged fill behind wing/headwalls.
5.1.B.6 Excavate behind wingwall and headwall total 24m X 4m X 1.25m.
5. 1.B.7 Cart nominal 180m3 loose spoil, surplus rock, removed vegetation and
demolished breakout concrete to approved to dump 5km lead.
5.1.B.8 Reinstate with PM3 QR or equivalent to 150mm below new sealed surface level .
5.1.B.9 Pour 150mm 32 mpa slab 40m X 4m (indented at headwall) SL72 mesh to reform
shoulder.
5.1.B.10 Reinstate bank areas up and downstream and under fenceline.
5.1.B.11 Coldmix (premixed a/c) along joint between slab and seal 40m.
5.1.B.12 Clean out and reinstate SW swale 3m wide X 15m long. Add rock armour nominal
50mm- X 125mm thick.
5.1.B.13 Clean out, remove spoil, reinstate scoured section on North West downstream
road embankment where the road was overtopped opposite South Terrace.
5.1.B.14 Allow one day excavator and roller time to clean out and reinstate approach
channels (2 of).
5.1.B.15 Signs and edgelines to be by Council.
5.1.B.16 (Re-) fencing to be organised by Council separately.

Details to be amended as necessary at Pre-tender Site Meeting.

5.2. MORCHARD EURELIA ROAD FLOODWAY
5.2.1 Reform swale drain NW side
5.2.2 Reform SW swale drain 20m long and cover with approved 75mm- armour rock and
nominal 25 mpa concrete
5.2.3 Reinstate side drain SE corner
5.2.4 Refill hollowed invert downstream 8m X 5m X 500mm with approved imported
armour rock 75mm5.2.5 Underpin undermined wall downstream with approved 75mm- armour rock and
nominal 25 mpa concrete 25m X 2m X 300mm and edge beam by thickening slab
300mm x 300mm nominal extra depth, but poured to suit reinstated rock bed
profile. Edge beam reinforced with 4 x 12mm deformed bars with 6mm ligatures at
1m centres.
5.2.6 Box out damaged seal 8m X 3m. Replace with approved PM2 20QR subbase and
32mpa concrete slab 180mm thick with layers of SL72 mesh top and bottom, 40mm
cover.
5.2.7 Match seal to slab with premix.
5.2.8 Other (if any) as determined at Pre-tender Site Meeting
5.3. JOHNBURGH ROAD CULVERT 45km from ORROROO

This is a major, high speed unsealed road, requiring at least a half road closure during
Works.

A Traffic Management Plan (TMP) will be required. If carried out by contract, the TMP
including the sequence of Works and ongoing adjustments to the proposed method of
managing traffic must be submitted to Council’s Works Manager for prior approval.
a) Upstream
5.3.1 Reshape and rock-armour both swales. Total 25m X 2.5m