Fresh Water Data - Page 2

RemovedHydroFrame dataset to accompany National water allocation statistics for environmental reporting; 2018 report.

www.mfe.govt.nz/publications/fresh-water/national-...

This report updates previously published statistics on water consented to be taken from surface and groundwater sources for consumptive uses (such as irrigation or drinking water). The report focusses on the potential pressure on surface water flows from consumptive water takes. Stream flow pressure is characterised by accumulating water consented to be taken as percentage of median flow in all river reaches affected by consented takes in New Zealand.

RemovedHydroFrame contains non-consumptive hydropower information.

This dataset reports modelled mean annual suspended sediment load reduction required to meet proposed suspended sediment attribute bottom lines. Results are reported for the REC 2 river reach scale as well as at the “catchment pourpoint average” scale. The dataset includes masks for the DoC estate as well as glacial mountain source of flow. For further information, see Hicks et al. (2019) Sediment load reductions to meet suspended and deposited sediment thresholds. NIWA Client Report No. 2019100CH. Prepared for the Ministry for the Environment.

Note that the river segment and pour point catchment results provided here (in the attached folders with the same names) form the basis for the erosion and economic modelling assessment of proposed sediment attributes as reported in Neverman et al. (2019). Impact testing of a proposed suspended sediment attribute: identifying erosion and sediment control mitigations to meet proposed sediment attribute bottom lines and the costs and benefits of those mitigations. Maanaki Whenua Landcare Research Client Report. Prepared for the Ministry for the Environment.

This dataset reports modelled reference and current state of streambed deposited fine sediment at the REC1 stream segment scale. It provides predicted reference state from a boosted regression tree model trained on 1.) reference site data defined by land cover rules, 2.) all available deposited sediment. It also shows predicted current state trained on all available deposited sediment data.

See Clapcott & Goodwin (2017) for further information on the relevant model rules and data inputs.

This dataset includes three “packages” of information, each with multiple variables. The packages include:

1. Load – results on mean annual suspended sediment load reported by REC 2 river reach scale for various model scenario variations.
2. Lakes – results on sediment inflow, outflow, and entrapment in lakes and reservoirs
3. Coastal – results on sediment inflows, trap efficiency, and sedimentation rates in coastal hydrosystems (estuaries)

For further detail on the modelling methods and discussing results, see Hicks, M., Semademi-Davies, A., Haddadchi, A., Shankar, U., Plew, D. (2019) Updated sediment load estimator for New Zealand. NIWA Client Report No. 2018341CH, prepared for Ministry for the Environment. January 2019. Available online: www.mfe.govt.nz/publications/fresh-water/updated-s...

Note that some portions of this dataset refine and update 2011 modelling on suspended sediment loads across New Zealand, whereas other components, especially the coastal package, report new modelling results.

This dataset reports erosion modelling results regarding annual mean sediment load reductions required to meet proposed suspended sediment attribute bottom lines. For more detail on the modelling process and methods, see Neverman et al. (2019). Impact testing of a proposed suspended sediment attribute: identifying erosion and sediment control mitigations to meet proposed sediment attribute bottom lines and the costs and benefits of those mitigations. Maanaki Whenua Landcare Research Client Report. Prepared for the Ministry for the Environment.

Results of modelled mitigations are reported at catchment scale and at the REC2 river reach scale. The modelled on-farm mitigations (per economic optimisation as reported in Neverman et al. (2019) are also mapped.

This dataset shows land that would be covered by the option 1 of section 8.4 Immediate action to reduce nitrogen loss.

This web map has been developed by the Ministry for the Environment to support policy proposals in the Action for Healthy Waterways discussion document. The proposals are currently being consulted on.

It provides extra detail on Option 1 in section 8.4 of the discussion document (Immediate action to reduce nitrogen loss). The map indicates the pastoral catchments and sub-catchments specified as high-nitrate in Option 1, where regional rules are not already in place or proposed, and shows the land considered to be low-slope.

Low-slope is defined in this option as land parcels with an average slope of less than 5, 7 or 10 degrees. We are seeking feedback on the appropriate slope threshold to use.

The catchments are those with the highest 10% of nitrate levels in the MfE Environmental Reporting River Water Quality dataset found here. Catchments where the predominant sources of nitrate are non-pastoral in origin are excluded.

Under Option 1, a per-hectare cap, or threshold, for nitrogen losses will be set for each sub-catchment with similar soil type and rainfall. This threshold will be based on a ranking of nitrogen losses from farms within each sub-catchment, and could be set at the 90th percentile, or the 70th, or a point between. Feedback is sought on where this threshold should be set.

This is only one of the options being consulted on, The areas indicated are provisional and may not equate to areas included in regulation.