Streambank erosion management The cost associated with bank erosion remediation varies between regions in the GBR and is reviewed in Bartley et al . ( 2015 ). Table 8 provides an estimate for each of the primary remediation options which was based on conversations with staff at several of the GBR Regional bodies ( specifically BMRG , Terrain , NQ Dry Tropics and FBA ) and published estimates from the region ( e . g . Lovett and Price , 2001 ). It is assumed that for each of more expensive options ( e . g . bank battering and toe revetment ) that fencing off and revegetation will also occur to provide additional support to the site in terms of long term tree root reinforcement . This extra vegetation is important insurance as Miller and Kochel ( 2013 ) found that 50 % of engineered structures ( e . g . grade control structures and bendaway weirs ) showed signs of impairment after 5 years .
Table 8 . Estimated costs of bank erosion remediation options assuming a 6 metre high bank with a 1 km long , 100 m wide riparian buffer (~ 10 ha ) on a property in B condition . Reproduced from : Bartley et al . ( 2015 ).
Activity |
Costs |
Fence off , natural vegetation regeneration & paddock management |
Fence off and active revegetation
Bank battering
Rip‐rap or rock revetment
Fencing |
$ 5000 / km |
$ 5,000 |
$ 5,000 |
$ 5,000 |
$ 5,000 |
Production loss |
A condition |
$ 387 / ha |
$ 3,870 |
|
|
|
( assuming highly productive treed land ) |
B condition |
$ 203 / ha |
$ 2,030 |
$ 2,030 |
$ 2,030 |
$ 2,030 |
C condition |
$ 100 / ha |
$ 1,000 |
Off‐site watering |
Tank $ 2,500 |
$ 8,700 |
$ 8,700 |
$ 8,700 |
$ 8,700 |
|
Trough $ 1,200 Polypipe $ 5000 / km |
|
|
|
|
Maintenance |
$ 250 / annum |
$ 250 |
$ 250 |
$ 250 |
$ 250 |
( floods / pigs / weeds ) a |
|
|
|
|
|
Revegetationb |
$ 27,900 / km |
|
$ 27,900 |
$ 27,900 |
$ 27,900 |
Bank battering |
$ 100,000 / km |
|
|
$ 100,000 |
$ 100,000 |
( generally for banks > 260 ) |
|
|
|
|
|
Rock‐revetment |
$ 5,000 / m or |
|
|
|
$ 5,000,000 |
for toes of bank (~ 6 m high ) |
$ 5,000,000 / km |
|
|
|
|
Total ( per km ) |
|
$ 15,980 |
$ 43,880 |
$ 143,880 |
$ 5,143,880 |
Risks |
Low |
Depends of frequency of overbank events |
Depends of frequency of overbank events
Moderate (~ 50 %) loss over 5 years a , b
Based on data in Lovett , S ., Price , P ., 2001 . Managing Riparian Lands in the Sugar Industry : A Guide to Principles and Practices . Sugar Research and Development Corporation / Land and Water Australia , Brisbane . Revegetation data was adjusted for inflation i . e . cost in 2001 estimated at $ 2,010 per 100 m is ~$ 2,790 per 100 m in 2013 .
C
Edwards and Star ( 2013 )
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