Glacial Deposits - Estimated Drawdown

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Metadata:


Identification_Information:
Citation:
Citation_Information:
Originator:
Groundwater Inventory and Mapping Project, a cooperative effort between the Water Bureau - Michigan Department of Environmental Quality, USGS - Michigan Water Science Center and Michigan State University - Institute of Water Research, RS&GIS and Biosystems and Agricultural Engineering. This project was mandated by P.A. 148 (Michigan Acts of 2003). Major funding was provided by MDEQ, supplemented with additional funds from the USGS Cooperative Water Program.
Publication_Date: October 28th, 2005
Title: Glacial Deposits - Estimated Drawdown
Geospatial_Data_Presentation_Form: raster digital data
Series_Information:
Publication_Information:
Online_Linkage: <http://gwmap.rsgis.msu.edu/>
Larger_Work_Citation:
Citation_Information:
Originator: Groundwater Inventory and Mapping Project
Publication_Date: August 18th,2005
Title:
Executive Summary - Public Act 148: Groundwater Inventory and Map Project
Edition: 1st
Geospatial_Data_Presentation_Form: Adobe PDF document
Online_Linkage: <http://gwmap.rsgis.msu.edu/>
Description:
Abstract:
The data points used to create this raster grid were obtained from Wellogic, the Michigan Department of Environmental Quality Statewide Groundwater Database (SGWD). Wellogic contains approximately 425,000 water well records found within the State of Michigan, and although it represents the best available data, it cannot be considered a complete database of all the wells or well records in existence. The well files were downloaded by county and merged together to create a statewide file. In the merge process any well that fell outside of its designated county boundary was removed from the original data set. Approximately 270,000 records were used in this file after the inconsistent point locations and bad data values were removed. A series of additional attributes were added to the database, this is a brief overview of how the well locations were processed:

A GIS data update utility created at MSU was used to process and merge the county wells; this also added many glacial drift and rock well fields, and percentages for aquifer drift material based on the existing Wellogic and lithology database information. Next the percentages of aquifer material and trend information were calculated for the drift index. These fields were used by the USGS to further calculate the wells transmissivity and yield values. Once these values were calculated a drawdown value could be derived. A detailed account of these processes can be found later on in this document.

Purpose:
To determine well drawdown for each 1 km2 grid cell, an analytical equation (Theis solution, see, for example, pg. 155, Fetter, C.W., Applied Hydrogeology, Fourth Edition, Upper Saddle River, N.J.: Prentice-Hall, Inc., 2001) was used to estimate the change in water level for a well 500 feet away from a proposed well continuously pumping at the estimated yield value for 100 days (assuming a storage coefficient typical of leaky-confined aquifers - 0.0016).

It is noteworthy that areas of low estimated drawdown (less than 5 ft) occur both where the estimated yield is moderate (70 - 200 gpm) and where it is low (< 10 gpm). In the low-yield areas, the small estimated drawdown results from the inability of the water-bearing materials to provide enough groundwater to impact a well 500 feet away. In areas of moderate yield, the available drawdown and transmissivity of the glacial deposits are such that the estimated yield can be obtained without significantly lowering the groundwater level 500 feet away. Note that in such areas, a high-capacity well capable of pumping at a rate larger than the estimated yield might be possible and such a well could impact groundwater levels 500 feet away.

Supplemental_Information:
Areas of thin glacial deposits (<30 feet thick) are shown because legally-constructed water wells screened in the glacial deposits of these areas are unlikely. The no-data areas on the map are zones more than 2000 meters away from a well record in Wellogic. This 2000-meter buffer zone balances the desire to note areas that lack data in Wellogic with the need for a statewide estimate. To flag these areas in this raster grid, negative values were assigned. Thin glacial deposits (<30 feet thick) were assigned a "-1" value. No-data areas were assigned a "-2" value.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: October 28, 2005
Currentness_Reference: publication date
Status:
Progress: Complete
Maintenance_and_Update_Frequency: None planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -90.172753
East_Bounding_Coordinate: -81.801049
North_Bounding_Coordinate: 47.533320
South_Bounding_Coordinate: 41.670939
Keywords:
Theme:
Theme_Keyword: Wells
Theme_Keyword: Wellogic
Theme_Keyword: Estimated Drawdown
Theme_Keyword: Transmissivity
Theme_Keyword: Yield
Theme_Keyword: Groundwater
Theme_Keyword: Grid surface
Place:
Place_Keyword: Michigan
Place_Keyword: State
Access_Constraints: No restrictions on access
Use_Constraints: No restrictions on use
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Justin M Booth
Contact_Organization:
Remote Sensing and GIS Research and Outreach Services, Michigan State University
Contact_Position: Information Technology Professional
Contact_Address:
Address_Type: mailing and physical address
Address: Geography Building, Michgan State University
City: East Lansing
State_or_Province: MI
Postal_Code: 48824
Contact_Voice_Telephone: (517)432-0446
Contact_Facsimile_Telephone: (517)353-1821
Data_Set_Credit:
Remote Sensing & GIS Research and Outreach Services - Department of Geography; Institute of Water Research; Biosystems and Agricultural Engineering, US Geological Survey, Michigan Water Science Center
Native_Data_Set_Environment:
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcGIS 8.3

Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
The estimated surface values are consistent with general trends across the state but aquifers in the glacial deposits tend to be heterogeneous, and in many areas in the State they are highly heterogeneous. Most glacial aquifers are identified only for very site-specific studies, and the horizontal and vertical continuity of glacial aquifers often are unknown.
Logical_Consistency_Report: None
Completeness_Report: None
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: Michigan Department of Environmental Quality
Publication_Date: May 25,2005
Title: Wellogic, Statewide Groundwater Database (SGWD)
Geospatial_Data_Presentation_Form: vector digital data
Series_Information:
Series_Name: Well location points
Publication_Information:
Publication_Place: Lansing, Michigan
Publisher: Michigan Department of Environmental Quality
Online_Linkage: <http://www.mi.gov/deq>
Online_Linkage: <http://www.mcgi.state.mi.us/mgdl/>
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: May 25, 2005
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: Wellogic
Source_Information:
Source_Citation:
Citation_Information:
Originator:
Center for Geographic Information, Michigan Department of Information Technology
Publication_Date: 2004
Title: Michigan Geographic Framework (MGF)
Edition: Version 4b
Geospatial_Data_Presentation_Form: vector digital data
Series_Information:
Series_Name: County Boundary File
Publication_Information:
Publication_Place: Lansing Michigan
Online_Linkage: <http://www.mcgi.state.mi.us/mgdl/>
Source_Time_Period_of_Content:
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: Framework v4b
Source_Information:
Source_Citation:
Citation_Information:
Originator:
David P. Lusch, Ph.D., Remote Sensing & GIS Research and Outreach Services, Michigan State University
Publication_Date: June 30th, 2005
Title: Michigan Glacial Landsystems
Edition: 1st
Geospatial_Data_Presentation_Form: vector digital data
Online_Linkage: www.rsgis.msu.edu
Source_Citation_Abbreviation: Landsystems
Process_Step:
Process_Description:
Well data by county was downloaded from the Michigan Geographic Data Library on May 24, 2005. All county files were renamed and processed to remove wells that fell outside of the county boundaries. The application uses Framework v4b county boundaries to clip out bad point locations and the MDNR public land survey section shape file to flag points that were outside of there survey sections. Other attributes were added such as elevation information, rock and drift well types, and drift aquifer percentages. Both a county and statewide Wellogic point shape files were created.
Source_Used_Citation_Abbreviation: Wellogic
Source_Used_Citation_Abbreviation: Framework v4b
Process_Date: May 24,2005
Process_Time: 4 hours
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Bill Enslin
Contact_Organization: Remote Sensing & GIS Research and Outreach Services
Process_Step:
Process_Description:
ArcInfo command line was used to run an AML joining the landsystems values to the modified Wellogic point shape files by county. This operation performs a spatial join using the coverage format.
Source_Used_Citation_Abbreviation: Landsystems
Process_Date: June 2005
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Howard W. Reeves
Contact_Organization: US Geological Survey, Michigan Water Science Center
Contact_Electronic_Mail_Address: hwreeves@usgs.gov
Process_Step:
Process_Description:
On the statewide Wellogic shape file, Drift Index trend information was calculated using fields created in step 1 and lithology information present in the Wellogic database. The calculations obtain and sum the percentages of aquifer material, marginal aquifer material, confining material, and partially confining material which gives us the percentage of representative aquifer material for all of the layers listed in the wells. The layers of the well are then compared to detect any trends in the aquifer material within the well. The trend information calculated is then parsed by county into a text file.
Source_Used_Citation_Abbreviation: Wellogic
Process_Date: June 2005
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Steve Miller
Contact_Organization:
Biosystems and Agricultural Engineering, Michigan State University
Contact_Electronic_Mail_Address: mill1229@msu.edu
Process_Step:
Process_Description:
Next, a series of scripts are run to equate landsystems values and trend information to the county well locations. Individual lithologic layers are assigned hydraulic conductivity values based on the landsystem assigned to the well. For each well, equivalent horizontal hydraulic conductivities are computed, and these hydraulic conductivities are multiplied by the saturated thickness of material at the well to estimate the transmissivity of the aquifer material at the well. The result of these calculations are two statewide well files that have transmissivity values and total thickness and a computed yield value defined by the pumping rate that would lower the water level at the well by fifty percent. The primary well file is for wells completed in glacial material and the secondary file is for rock wells used to characterize the glacial deposits overlying the bedrock.
Source_Used_Citation_Abbreviation: Wellogic
Process_Date: June 2005
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Howard W. Reeves
Contact_Organization: US Geological Survey, Michigan Water Science Center
Contact_Electronic_Mail_Address: hwreeves@usgs.gov
Process_Step:
Process_Description:
The transmissivity and yield datasets are Kriged within each landsystem to interpolate and extrapolate the point values of both transmissivity and yield to 1000 m x 1000 m grids for each point file. Statewide transmissivity and yield surfaces from the Kriging estimates for each landsystem are merged by glacial wells and glacial over the rock wells.

Wherever glacial wells have adequate coverage they will take precedence over glacial deposits overlying the bedrock wells. This is decided by buffering out 2000m on each well file. The buffered glacial wells are used as the analysis mask for the grid surfaces (Yield and Transmissivity), all other areas are back filled with the 2000m buffered glacial deposits overlying the bedrock wells.

It should also be noted that all islands were removed from the State because inadequate amounts of well locations were present to estimate a grid surface.

Data masks were used by identify areas where the glacial deposits are less than 30 ft thick and to identify areas that are more than 2000m away from any well in the Wellogic database.

Source_Used_Citation_Abbreviation: Landsystems
Source_Used_Citation_Abbreviation: Wellogic
Process_Date: June 2005
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Justin M Booth
Contact_Organization:
Remote Sensing and GIS Research and Outreach Services, Michigan State University
Process_Step:
Process_Description:
With the two grids surfaces complete (Yield and Transmissivity), drawdown can be estimated. To determine well drawdown for each 1 km2 grid cell, an analytical equation (Theis solution, see, for example, pg. 155, Fetter, C.W., Applied Hydrogeology, Fourth Edition, Upper Saddle River, N.J.: Prentice-Hall, Inc., 2001) was used to estimate the change in water level for a well 500 feet away from a proposed well continuously pumping at the estimated yield value for 100 days (assuming a storage coefficient typical of leaky-confined aquifers - 0.0016).

This surface shows the projected impact of a new well on neighboring wells to allow users of the information to assess potential well interference as addressed in Public Act 177 (Michigan, 2003b). This estimated impact is only a general estimate and should not be used for licensure or legislative purposes. It serves as guidance and illustrates the anticipated general pattern of impacts on neighboring wells due to pumping across the State.

For more information on the process visit : <http://gwmap.rsgis.msu.edu/>

Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Howard W. Reeves
Contact_Organization: US Geological Survey, Michigan District
Process_Step:
Source_Used_Citation_Abbreviation: P:\Final_products\Glacial_Deposit\drawdown_grids\ddown_web
Process_Step:
Process_Description: Dataset copied.
Source_Used_Citation_Abbreviation: P:\Final_products\Glacial_Deposit\drawdown_grids\gd_drawdown

Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Raster
Raster_Object_Information:
Raster_Object_Type: Grid Cell
Row_Count: 644
Column_Count: 631
Vertical_Count: 1

Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Map_Projection:
Map_Projection_Name: Oblique Mercator
Oblique_Mercator:
Scale_Factor_at_Center_Line: 0.999600
Oblique_Line_Azimuth:
Azimuthal_Angle: 337.000000
Azimuth_Measure_Point_Longitude: -86.000000
Latitude_of_Projection_Origin: 45.309167
False_Easting: 2546731.496000
False_Northing: -4354009.816000
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: row and column
Coordinate_Representation:
Abscissa_Resolution: 1000.000000
Ordinate_Resolution: 1000.000000
Planar_Distance_Units: meters
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: Geodetic Reference System 80
Semi-major_Axis: 6378137.000000
Denominator_of_Flattening_Ratio: 298.257222

Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: Estimated drawdown
Entity_Type_Definition:
Drawdown at 500 ft. was calculated for each cell using the estimated yield values, assuming 100 days of continuous pumping and a storage coefficient of 0.0016 consistent with a leaky aquifer.
Attribute:
Attribute_Label: ObjectID
Attribute_Definition: Internal feature number.
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: Value
Attribute_Definition: Glacial deposit estimated drawdown values in feet
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: -2
Enumerated_Domain_Value_Definition: No-data areas
Enumerated_Domain:
Enumerated_Domain_Value: -1
Enumerated_Domain_Value_Definition: Thin glacial deposits (<30 feet thick)
Enumerated_Domain:
Enumerated_Domain_Value: 0-155
Enumerated_Domain_Value_Definition: Estimated drawdown values
Attribute:
Attribute_Label: Count

Distribution_Information:
Resource_Description: Downloadable Data
Distribution_Liability:
The State of Michigan or the Ground Water Inventory and Mapping Project partnership assumes no liability for results or conclusions drawn from use of this data
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Transfer_Size: 0.185

Metadata_Reference_Information:
Metadata_Date: 20051028
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Remote Sensing and GIS Research and Outreach Services, Michigan State University
Contact_Person: Justin M Booth
Contact_Position: Information Technology Professional
Contact_Address:
Address_Type: physical address
Address: Geography Building, MSU
City: East Lansing
State_or_Province: MI
Postal_Code: 48824
Contact_Voice_Telephone: (517)432-0446
Contact_Electronic_Mail_Address: boothj@msu.edu
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Metadata_Extensions:
Online_Linkage: <http://gwmap.rsgis.msu.edu/>
Profile_Name: ESRI Metadata Profile
Metadata_Extensions:
Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>
Profile_Name: ESRI Metadata Profile

Generated by mp version 2.8.6 on Fri Oct 28 14:59:53 2005