Tylr Naprstek Water Modeling Coordinator

Transcription

1 Tylr Naprstek Water Modeling Coordinator

2 Focus development of Regional GW model for 2 basins: Loup, Elkhorn

3 Niobrara R to Platte R Headwaters of Loup/Elkhorn to Columbus/Norfolk

4 NebrGISgeology.asp Encompasses most of the sandhills region Unique to Nebraska Abundant Aquifer (1,200 ft) High recharge potential

5 Elkhorn & Loup originate and end in Nebraska No State Compacts Landlocked NRDs In-Stream Flow Requirement Appropriation A-17331, NGPC 3,700 Louisville, NE. (11/30/1993) Develop a water budget for the region Long-term stream impacts to a basin and the Stream Depletion Factor (10%-50 year line) State determined line for hydrologically connected areas resulting in additional management

6 Model Work, Funding, & Data Funding, Data Input & Management Use Funding & Data Input Technical Data UNL School of Natural Resources Conservation and Survey Division

7 Streamflow measurements Gage Data 2006 Measurements NHD dataset t CSD testholes Groundwater Level Change Measurements Additional testhole & Geophysics work Flowmeter Readings Irrigation Wells & Canal Datasets Historical Precipitation

8 38 Stream Gages with detailed historical data (daily, monthly, annual)

9 Additional measured flow targets Fall 2006

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11 GIS used to locate Geophysic sites/testholes Data formulates base of aquifer map

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14 Top of Brule or Pierre (and in some cases Niobrara) High electrical conductivity Low hydraulic conductivity Need to see through thick stack of sand + Ogallala

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17 Started diversions in 1895 Canal seepage recharge impacts water levels/stream flows Significant impact to water budget Department of Natural Resources & USGS used NHD shapefile to indicate locations of canals No Laterals indicated Canals meandered wrong

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19 USGS requested more precise locations Historical & current laterals Wasteways (return flows) Exact Diversion i Points GPS/GIS handhelds used to correct and refine Field time spent with irrigation personnel locating exact locations Substrate identified Cement, lining, soil, etc.

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27 Pre Calibration Predictive Analy sis

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29 Modflow Grids do not have correction lines Legal Sections do

30 As Model becomes more complex, grid size changes (shrinks, adjusts, etc.)

31 Challenge: Join layers Grid Size and Legal to get usable data per section Solution: Right-click layer, create join, join data based on spatial location Create Summary of data Average, sum, min, max, variance, standard dev. Outcome: Districts have sectional summary of modeling grid

32 LB 483 passed in 2009 Introduced by Senator Langemeier of Schuyler Allows controlled development of 10,000 ground water acres per NRD over 4 year period Designed as a response to initial designation then reversal of Lower Platte Basin being Fully Appropriated

33 LLNRD developed a criteria sheet for all new acre applications Points are assigned based on how an application fits within criteria Applications are redrawn using GIS based on landowner field boundaries on aerial photographs Shapefile for each application created LLNRD staff apply District approved ranking sheets to score applications Unbiased Few ties

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36 Quantile Classification: An equal number of values are assigned in each class. All classes have the same number of features.

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38 Point totals are assigned based on each criteria 2009: 12,951 applied acres 2,003 approved applications scored > : 11,958 applied acres 2,179 approved applications scored > Each approved site was visited i by NRD staff and shapefiles added to District acre certification

39 Current NRD Processes involving the model Irrigated Acre (1.3 Million) Rights Transfers SDF Variances to Rules and Regulations SDF LB483 SDF Density of development SSURGO 6,000 acres to approve 2011,2012

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41 Internet Search: Elkhorn-Loup Model Phase 1&2 reports published Shapefiles: Base of Aquifer, Stream Depletion Factor Other related publications Contacts: Lower Loup Natural Resources District Tylr Naprstek, Coordinator (308) USGS N b k W S i C USGS Nebraska Water Science Center Jennifer S Stanton, Water modeler (402)

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