FLOOD06961

• County: Jefferson
• Community: Littleton
• Stream Name: Massey Draw and SJCD South
• Basin: South Platte
• Title: Conceptual Design Report for Massey Draw and SJCD ‎(South)‎ Mjor Drainageway Planning Update
• Date: 2/1/2006
• Prepared For: Jefferson County
• Prepared By: Olsson Associates
• Floodplain - Doc Type: Floodplain Report/Masterplan

8 City of Littleton

List of Tables

Table ES-1
Table ES-2
Table ES-3
Table ES-4
Table ES-5
Table 1
Table 2
Table 3
Table 4
Table S

Table 6

Table 7
Table 8
Table A-1
Table A-2
Table A-3
Table A-4
Table A-S
Table B-1
Table B-2

Table B-3

List of Figures

Figure ES-1
Figure ES-2
Figure 1
Figure 2
Figure A-1
Figure A-2

CY\

Massey Draw and SJCD (South! Major Drainageway Planning Update
Conceptual Design Report
February 2006

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List of Figures (cont.)

List of Drawings

Agencies Invited to Participate in Master Plan Process............................................. ES-1
Master Plan Participating Organizations and Representatives.................................. ES-1
100-year Peak Flows at Select Locations ................................................................. ES-2
Cost Summary by Jurisdiction................................................................................... ES-4
Master Plan Improvements Costs and Benefits......................................................... ES-S
Comparison of Watershed Areas, Original Plan vs. Master Plan Update ..................... 3-1
One-Hour Rainfall Depths ....... ..... ...... .................. ..... ............ ....... .... ............................ 3-1
100-Year Flows Reported in UDFCD Memorandum .................................................... 3-2
100-Year Flows from Flood Insurance Study............................................................... 3-2
Comparison of tOO-Year Flows: Target Flows, Calibration Model,
and Modified Baseline Model....................................................................................... 3-2
Estimated Street Overtopping between Carr and Garrison Streets on SJCD (South)

Tributary No. 1 .............................................................................................................4-4

Master Plan Improvements Costs and Benefits............................................................ 6-2
Cost Summary by Jurisdiction...................................................................................... 6-7
CUHP Subwatershed Characteristics, Massey Draw .................................................A-1S
CUHP Subwatershed Characteristics, SJCD (South).................................................A-17
UDSWM Conveyance Element Parameters, Massey Draw........................................A-18
UDSWM Conveyance Element Parameters, SJCD (South) .......................................A-21
Baseline Peak Flows for Massey Draw and SJCD (South) ........................................A-23
Summary of Observations ........................................................................................... B-1
Improvements with Costs and Benefits Recommended in the Alternatives
Evaluation Report (Selected Plan) ............................................................................... B-6

Unit Costs. ................................................. .............. ........... ........ ............. .................. B-1 0

Figure A-3
Figure A-4
Figure A-S
Figure A-6
Figure A-7
Figure A-8
Figure A-9
FigureA-10
Figure A-11
Figure A-12
Figure A-13

Figure A-14
Figure B-1
Figure B-2

Sheet No.
Index
1
2
3
4
5
6
7
8
9
10
11

Project Vicinity Map
Master Plan Recommended Improvements
Project Vicinity Map
Master Plan Recommended Improvements
Subwatershed Delineation and Conveyance Elements (West Study Area)
Subwatershed Delineation and Conveyance Elements (East Study Area)

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Watershed Imperviousness (West Study Area)
Watershed Imperviousness (East Study Area)
Hydrologic Soils Group Map (West Study Area)
Hydrologic Soils Group Map (East Study Area)
UDSWM Routing Schematic, Massey Draw (West Study Area)
UDSWM Routing Schematic, Massey Draw (East Study Area)
UDSWM Routing Schematic, SJCD (South)
Massey Draw 100-Year Hydrographs
North Tributary Massey Draw and SJCD (South) 100-Year Hydrographs
SJCD (South), North Tributary and Tributary NO.1 100-Year Hydrographs
Modified Baseline Peak Flow vs. Stream Station, Massey Draw and North Tributary Massey
Draw
Modified Baseline Peak Flow vs. Stream Station, SJCD (South) and Tributaries
Existing Facilities
Selected Plan

Description

Stations

Plan and Profile Massey Draw
Plan and Profile Massey Draw
Plan Massey Draw / Golf Course Split
Profile Massey Draw / Golf Course Split
Plan Massey Draw / Rockland Dr. Split
Profile Massey Draw / Rockland Dr. Split
Plan and Profile Massey Draw
Plan and Profile Massey Draw
Plan and Profile Massey Draw
Plan and Profile Massey Draw
Plan Massey Draw
Plan North Tributary Massey Draw
Profile North Tributary Massey Draw

252+00
222+00

to
to

278+08
252+00

138+S0 to 162+00
109+00 to 138+50
79+00 to 109+00
49+00 to 79+00
19+00 to 49+00
0+00 to 14+50
0+00 to 14+50

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