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North Cowra-Mulyan Park - Trunk Drainage Feasibility

We have been instructed by Cowra Shire Council to investigate the feasilility of a Trunk Drainage/Detention Basin System for the catchment which is upstream of and passes through the Mulyan Park area of North Cowra. The need for such investigation arises from a history of nuisance flooding in that area. It is evident that this flooding problem will worsen as the catchment continues to be developed for residential purposes. At present the catchment is only approximately 50% developed.

Council wishes to formulate and adopt a strategic programme for the implementation of an appropriate drainage system as part of the ongoing development of the area.

Wherever possible, it is intended to adopt the criteria as specified in Council's brief. However, following initial assessment of the catchment and its existing structures and after further discussions with Council officers, it was agreed that additional parameters were required. The following are the revised aims and objectives:

  1. Wherever possible retain existing drainage facilities by providing upstream retardation to control flows.
  2. Adopt a general low flow Average Recurrence Interval (A.R.I.) of 1 in 5 years. That is, flows up to this event are to be contained wherever possible within the existing or proposed pipe systems.
  3. Flows from events between the 1 in 5 year and the 1 in 100 year A.R.I. are to be contained and controlled within open grassed channels which generally follow the alignment of the piped system.
  4. Determine the size, depth, nature and most suitable locations for retardation basins which will control discharge rates such that the resulting flows can be contained within the existing structures or proposed structures of a reasonable size.
  5. Recommend a staged scheme which will take into account future development as it occurs and the determination of any additional land requirements.
  6. Recommendations as to what controls and restrictions can be placed on subdivisional development to ensure that the adopted drainage system and that development are compatible.
  7. Determine the economics and cost effectiveness of the recommended scheme.

Additional Information

Field Value
Title North Cowra-Mulyan Park - Trunk Drainage Feasibility
Publication Date 1 August 1990
Themes Land and Resource Management
Spatial Extent
Map data © OpenStreetMap contributors
Council/LGA Cowra Shire Council
Author/ Prepared by J Wyndham Prince & Associates Pty Ltd
Publish date 26 June 2020
Update date 26 June 2020
River Basin 412 - Lachlan
Approval State Approved
Submitted for approval 26 June 2020
Submitted by Akhil Sud
Approved 26 June 2020
Approved by dstazic
Identifier 073026b9-c790-4297-a33c-915704bf4f4b