HomeMy WebLinkAboutDan Corbin, Inc.-Engineering Agreement-01.20.2009 fte„o ` . Poo5-? 5
Dan Corbin,Inc. r
28 River Ridge Lane — Cell: (319)23 I J047
Cedar Falls,IA 50613 Fax: (319)266-3398
Inc. E-Mail: dcorbin@cfu.net
January 8th 2009RiVti
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009
CITY ENGINEER
Jamie Knutson, P.E.
STEM.®,IN
City of Waterloo, Engineering Dept.
Waterloo City Hall
715 Mulberry St.
Waterloo, Iowa 50703
Re: NSSDA Vertical Accuracy of 2008 DTM
Dear Jamie,
We have completed the re-testing of the revised digital terrain model (DTM) for
the northwest quarter and the southwest quarter of the City. In addition to
retesting the original test points we also added a series of new test points.
The NW quarter tested at 0.37ft vertical accuracy at the 95% confidence level.
The SW quarter tested 0.58ft vertical accuracy at the 95% confidence level.
Both quarters now meet the 1.0ft vertical accuracy at the 95% confidence level.
Enclosed is the following:
• Quad 1 (NW qtr)
o NSSDA Vertical Accuracy Statistic Worksheet.
O 1"=3,600ft plot of test site locations.
O 1 set of 50sc color test site plots.
O 1 set of color test site prints.
• Quad 4 (SW qtr)
o NSSDA Vertical Accuracy Statistic Worksheet.
O 1"=3,600ft plot of test site locations.
O 1 set of 50sc color, test site plots.
O 1 set of color test site prints.
Also enclosed is your invoice #304 dated 01-08-09 for the work completed on the
re-testing of the vertical accuracy.
Page 1 of 2
Please contact me if you have any questions concerning the testing
procedures/results and/or the invoice.
Sincerely,
Dan Corbin, President By:
Dan Corbin, Inc. The ity of Waterloo Ti 0 us tei
28 River Ridge Lane
Cedar Falls, IA 50613 Date: ) g C-6 9
Email: dcorbinAcfu net
Ph (319) 268-1665
Fx (319) 266-3398
Page 2 of 2
Da
n Corbin, Inc. Invoice
28 River Ridge Lane
Cedar Falls, IA 50613 Date Invoice#
Ph: 319-268-1665
Fax: 319-266-3398 1i8i2009 304
Bill To
Jamie Knutson,P.E.
Engineering Department
Waterloo City Flail
715 Mulberry St
Waterloo,Iowa 50703
Description Quantity Rate Amount
Photogrammetric Consulting Services
Independent accuracy verification of the 2008 digital terrain model(DTM)
NSSDA vertical accuracy re-testing of the NW and SW quarters of Waterloo 4,181.00
4,181.00
Make your checks payable to DAN CORBIN,INC.
Total due in 15 days. 18%APR on unpaid balances. Terms Total $4,181.00
Thank you for your business. Net 15 I Balance Due $4,181.00
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