The shapefile associated with this metadata file represents the spatial distribution of mean annual water-budget components, in inches, for the Island of Maui, Hawaii. The water-budget components in the shapefile were computed by a water-budget model for a scenario representative of predevelopment conditions (1978-2007 rainfall and 1870 land cover), as described in USGS Scientific Investigations Report (SIR) 2015-5164. The model was developed for estimating groundwater recharge and other water-budget components for each subarea of the model. The model-subarea dataset, consisting of 318,429 subareas (polygons), was generated using Esri ArcGIS software by intersecting (merging) multiple spatial datasets. Spatial datasets merged includes those that characterize the spatial distribution of hydrologic and physical conditions (rainfall, fog interception, irrigation, reference evapotranspiration, direct runoff, soil type, and land cover) that the model uses to compute groundwater recharge and other water-budget components. Additional spatial datasets merged into the model-subarea dataset include those of select geographic features that assist in analyzing model results. This metadata file describes the process of merging these spatial datasets. The shapefile attribute information associated with each polygon present an estimate of mean annual rainfall, fog interception, irrigation, septic-system leachate, runoff, canopy evaporation, actual evapotranspiration, storm-drain capture, net precipitation, total evapotranspiration, recharge, and seepage from reservoirs and cesspools. This shapefile also includes select geographic and land-cover attributes of the polygons. Brief descriptions of the water-budget components and attributes are included in this metadata file. Refer to USGS SIR 2015-5164 and SIR 2014-5168 for further details of the methods and sources used to determine these components and attributes.
The water-budget components in this shapefile were determined as part of a study to estimate the spatial distribution of groundwater recharge on the Island of Maui, Hawaii, for a scenario representative of predevelopment conditions (1978-2007 rainfall and 1870 land cover), as described in USGS SIR 2015-5164. The recharge estimates may be used in numerical groundwater models that can evaluate the effects of groundwater withdrawals on groundwater levels, streamflow, coastal discharge, and salinities in public and private wells on Maui.
|Title||Mean annual water-budget components for the Island of Maui, Hawaii, for predevelopment conditions, 1978-2007 rainfall and 1870 land cover (version 2.0)|
|Authors||Adam G. Johnson|
|Product Type||Data Release|
|Record Source||USGS Digital Object Identifier Catalog|
|USGS Organization||Pacific Islands Water Science Center|
Volcanic aquifers of Hawai‘i—Hydrogeology, water budgets, and conceptual models
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