HomeMy WebLinkAbout961687.tiff RESOLUTION
RE: APPROVE FLOOD HAZARD MITIGATION PLAN FOR COMMUNITY OF
WATTENBERG
WHEREAS, the Board of County Commissioners of Weld County, Colorado, pursuant to
Colorado statute and the Weld County Home Rule Charter, is vested with the authority of
administering the affairs of Weld County, Colorado, and
WHEREAS, the Board has been presented with a Flood Hazard Mitigation Plan for the
Community of Wattenberg from the County of Weld, State of Colorado, by and through the
Board of County Commissioners of Weld County, on behalf of the Weld County Office of
Emergency Management, with terms and conditions being as stated in said plan, and
WHEREAS, after review, the Board deems it advisable to approve said plan, a copy of
which is attached hereto and incorporated herein by reference.
NOW, THEREFORE, BE IT RESOLVED by the Board of County Commissioners of
Weld County, Colorado, that the Flood Hazard Mitigation Plan for the Community of Wattenberg
from the County of Weld, State of Colorado, by and through the Board of County
Commissioners of Weld County, on behalf of the Weld County Office of Emergency
Management, be, and hereby is, approved.
The above and foregoing Resolution was, on motion duly made and seconded, adopted
by the following vote on the 23rd day of September, A.D., 1996.
BOARD OF COUNTY COMMISSIONERS
WD COUNTY, COL7ADO 4 EL M, 4
Barbara J. KirkmeyeChair
1861 4Q� °�'� � ty Clerk to the Board
-� Li .�� e . axer, Pr -Te
eputy Clef to the Board
Dale K.Hall
APP AS TO FO M: L ,O� e:1_, —u1.-7--c—
Constance L. Harbert
my Att ne // ,, ) �
W. H! ebster
961687
(L' : DE71 PL," Kt3 EM0006
FLOOD HAZARD MITIGATION PLAN
COMMUNITY OF WATTENBERG
WELD COUNTY
COLORADO
KISTNER AND ASSOCIATES
AUGUST 1996
961687
FLOOD HAZARD MITIGATION PLAN
FOR THE
COMMUNITY OF WATTENBERG
WELD COUNTY
COLORADO
PREPARED BY
KISTNER AND ASSOCIATES
JOHN PLAKORUS
PROJECT MANAGER
961687
WATTENBERG, COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
TABLE OF CONTENTS
Introduction 1
Purpose of Study 1
Scope of Study 1
Wattenberg Flood Vulnerability 1
Wattenberg Setting 2
Community Description 2
Geographical Setting 3
1995 Flood Event 3
Damage Assessment 4
River and Flood Characteristics 4
South Platte Basin and Stream Characteristics 4
What is a 100- Year Flood Event? 4
Types of Floods 6
Flood History of Wattenberg and Weld County 6
Planning and Zoning 9
Weld County Planning Department 9
Authority to Plan 10
Weld County Zoning Ordinances 10
Flood Hazard Mitigation Activities 11
Flood Protection Measures to Date 11
The National Flood Insurance Program 11
Wattenberg and Weld County Flood Mitigation
Action Plan Recommendations 13
Appendix 1: Flood Hazard Development Permit Procedure 15
Appendix 2: Spotter Network 16
961.687
WATTENBERG, COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST1996
Appendix 3: Floodproofing for Homeowners and Business 18
Appendix 4: In the Event of a Flood:
Tips to Minimize Loss of Life and Property 20
Appendix 5: Sources of Assistance 23
References 24
961657
WATTENBERG,COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
INTRODUCTION community under investigation and the
larger region. Both short-term and long
term opportunities for Flood Hazard
Mitigation are considered.
Purpose of Study
Colorado residents continue to lose Wattenberg Flood Vulnerability
thousands of dollars in public and private
The community of Wattenberg is vulnerable
investment due to flooding each year.
Wattenberg, Colorado is a small Front to flooding, as it has been demonstrated in
Range unincorporated community of Weld the past - 1965, 1973 and 1985. During
County that is vulnerable to flooding. The these historic flood events, weather
purpose of this Flood Hazard Mitigation conditions, topography, hydrology and
Plan is to identify and discuss critical flood geography have combined to create
hazard issues faced by the community and to hazardous and damaging situations. It is
present opportunities for concerted action. It crucial, therefore, that Wattenberg take
steps, today, to lessen the effects of future
is a plan that seeks to accomplish two
specific goals: First, it brings together the floods tomorrow. This can best be
many diverse elements of flood hazard accomplished through a combination of
research and floodplain analysis that have increased community awareness, flood
been completed over the years for Weld preparedness and mitigation planning.
County and its major river basin, the South
Platte; Second, it provides specific flood Effective flood mitigation planning relies
mitigation opportunities (structural and non- upon an assessment of the natural and
structural) intended to reduce the severity of physical environment along with the
future flood events in Wattenberg.
The Wattenberg Flood Hazard Mitigation Lupton Bottoms Ditch
Plan has been prepared with the generous
help of many people including local
community members and County officials.
It will require the continued cooperation of go;,,
these individuals to ensure that the hazard PI
mitigation proposals presented in this plan •
's
are carried through.
Scope of Study
CRS
This Flood Hazard Mitigation Plan is I I
ailatteitherg
focused primarily upon high flood areas /
within the unincorporated limits of the
community of Wattenberg (See Figure 1). r
The hazard analysis is not, however, limited
to the floodplain of Wattenberg, CR
comprehensive mitigation studies must take Figure 1
into account the geographic setting of the
96kt8?
WATTENBERG, COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
WYOMING f NEBRASKA
historical relationship of the community to J/
the region as a whole. As a result this Flood
Mitigation Plan will address key elements of WELD COUNTY
the historical, geographical and regional 85
factors that will influence the impacts of 25
future flood events.
'Fo t Collins
•
eeleyy. Morgan
THE WATTENBERG SETTING pike
'ver
76. Fort Morgan
•
Community Description
att rg
Wattenberg is a small unincorporated B gMon Adams
community situated in the southwestern
section of Weld County, approximately two Figure 2
miles north of the city of Brighton and
thirty-five miles south of the city of Greeley. approximately twenty-five percent per
Today, Wattenberg is primarily a residential decade, which is more than triple the
community with many of its citizens national average. Approximately eighty-five
commuting to either Brighton, Denver, or Ft. Percent of the population is located in an
800 square mile area in the southwestern
Lupton for employment. The community
portion of the county. The 1990 population
population is currently listed as 250
permanent residents according to the 1990 density for this area is approximately 149
people per square mile. In 1990, 131,821
Census. Within the community there is a
church, which also serves as a community people lived in Weld County, which
center and the remainder of the structures represents four percent of the Colorado's
are single family homes or commercial population.
properties.
Historically, Weld County has been
considered an agricultural county. However,
To gain a better understanding of
Wattenberg. it is imperative to understand according to the 1990 census less than forty
percent of the county was classified as
Weld County as a whole. Weld County is
agriculture. While the trend for the counties
located in the northeastern portion of the
state, in the Great Plains area approximately economy is toward diversification, the core
40 miles east of the Continental Divide. economic activity will continue to be
Bounded by Wyoming on the north, Logan derived from farming. The 1990 labor force
and Morgan Counties to the east, Adams in Weld County was divided between
County to the south, and Boulder and different industries as follows:
Larimer Counties to the west, Weld County ' Agriculture and mining
contains approximately 4,004 square miles • Government
and is the third largest county in the State of • Manufacturing
Colorado (See Figure 2) • Professional and related services
• Self employed, and
The growth rate in Weld County has been • Wholesale and retail
2
961'.6,947
WATTENBERG,COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
(Source: Colorado Department of Labor and culverts and roadways were damaged in
Employment, 1994) Weld County (See Figure 3).
The significance of the County's growth and
economic diversification can be seen in the ► "
increases of urban type uses in historically Allland area dedicated to agriculture. Urban •
growth not only creates pressure on e4a 1 w
farmland, but also on floodplains throughout
the county.
S%
Geographical Setting
Weld County has elevations ranging 4,400
feet above sea level to highs of 6,600 feet in
the northwestern portion of the county. Road Closures - 1995 Flood
Gently rolling hills form the terrain in Weld
County, primary used for agriculture and Hardin Area
cattle grazing. Weld County climate Weld County Road(WCR)80 between WCR 50 and WCR
61
experiences wide temperature changes from WCR 388 between HWY 37 and WCR 380
season to season and rapid weather changes WCR 63 between HWY 34 and WCR 380
WCR 65 between WCR 50 and WCR 380
due to storms traveling throughout the WCR 50 between HWY 34 and WCR 380
region. The annual average mean WCR 52 between WCR 61 and WCR 380
temperature in Weld is 48.4 degrees. The Other Areas
WCR 61 between HWY 34 and WCR 50
average rainfall amount is 11.96 inches and WCR 50between WCR 59 and WCR 61
the average snowfall is 32.3 inches per year. - WCR 51 between HWY 34 and WCR 58
WCR 49.5 between HWY 34 and WCR 58
WCR 46 between WCR 35 and WCR 37
WCR 33 between WCR 40 and WCR 42
THE 1995 FLOOD EVENT WCR 34 between WCR 25 and US 85
WCR 25.5 between WCR 32.3 and WCR 34
WCR 40 between WCR 31 and WCR 33
WCR 25.5 between WCR 36 and WCR 38
During the spring of 1995, Colorado and WCR 68 between WCR 89 and WCR 67
WCR 29 between WCR 38.5 and WCR 42
specifically Weld County experienced WCR 45 between WCR 44 and WCR 42
exceptionally high waters along the South WCR 50.5 between WCR 39 and WCR 41
Platte river drainage, due to rains and high WCR 42 between WCR 33 and US 85
WCR 89 between WCR 64 and WCR 68
snowmelt and subsequent runoff. The high WCR 25.5 between WCR 36 and WCR 38
water and runoff started approximately May WCR 105 between WCR 80 and WCR 86
Closed 6/1095
30th and went to June 20th. The majority of
WCR 396 between 54i'St.Rd.and WCR 27.5
the concern was along the South Platte River 54'"St.Rd.between Alto Way and 65'"
but several bridges were affected on the Closed 6/12/95
Cache LaPoudre River. Heavy rains WCR 30.5 between WCR 23 and HWY 66
Closed 6/14/95
between June 7111 and 15th caused extensive WCR 13 between WCR 26 and WCR 28
damage to Weld County roads , bridges and Figure 3
culverts in areas not normally effected by
water runoff. Approximately 122 bridges,
3
96_'.x:s;'7
WATTENBERG,COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
Damage Assessment relatively uniform, slowly transitioning from
about 9 feet per mile in the upstream reaches
As statewide flood damage cost exceeded to about 6 feet per mile downstream.
$38 million, Governor Romer allocated $2.9
million to public -works projects throughout The drainage area of the South Platte varies
Colorado. In late August, following the considerably from the Adams-Weld-Morgan
damage survey, state officials allocated County line due mainly to the number of
$100,000 to Weld County Commissioners relatively large tributaries draining the
for road and bridge repairs. With a total eastern slope of the Rocky Mountains (See
repair bill of more than $1,000,000, the state Figure 4). At Ft. Lupton, the nearest gauge
funds only minimally funded the projects. location to Wattenberg, the drainage area is
5,010 square miles.
Following the Flooding of 1995 the
Community of Wattenberg conducted Flooding along the South Platte River in
meetings to determine a mitigation program Wattenberg and surrounding areas normally
for their area to alleviate potential future occurs from May through August, with the
flooding. Although, no significant damage most frequent flooding occurring during
was reported in Wattenberg in the Flood of June. Serious floods however, have
1995, the community feels that next time it occurred from February through December.
could be their turn. Though the South Platte River flooding is
the focal point concerning potential flood
damage, flood damage has occurred due to
small culvert sizing, and the silting up of
RIVER AND FLOOD local drainage channels.
CHARACTERISTICS
What is a 100 year Flood Event?
South Platte Basin and Stream The science of predicting the effect of floods
Characteristics on lives and property falls largely to
hydrologists. They estimate future floods by
Wattenberg is directly affected by the South studying the past behavior of a stream.
Platte River just east of the community. The Floods are categorized according to their
return interval-l0-, 50-, 100-, and 500 year
South Platte River flows in a general
northernly direction from the Adams-Weld floods. Each flood interval is related to
County line to apporximately Miliken,
percent chance that a flood may actually
Colorado where it turns and flows in a occur within a given year (See Figure 5).
northeasternly direction. Throughout the This has caused considerable confusion at
reach in Wattenberg and Weld County area
times: a 100-year flood does not happen
the South Platte Rover flows in a relatively
well defined channel. This channel is with absolute regularity every 100 years.
typically braided and is situated in a broad Rather, a 100-year flood may occur at any
shallow valley ranging in width from about time within a given year. Colorado State
3,000 feet to about 9,000 feet and is flanked law, however, requires that the 100-year
floodplain be used for land use regulations
by rolling plains. The streambed slope of
the South Platte River in Weld County is
4
961667
WATTENBERG, COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
P /
1
I
ir
/
et II°
1
♦ I ! ,
P� ' •°' ' t Y Hi
'.i E U
Z
00
I o . FAu i
1 °
= BASIN BOUNDARY
I • B o Z —L_
l i i
/ F' is o \ I z
°� u `�_ o
' u Q
� tf it \it
Z/Z�
Yo
R
ICC I :1 o \
� / dry � - „ : a...". o
�.g •• \ ° -\ltd •p 77 °
�`
\ Z( ° • � •
BSI P ' 1..�
o ° s °a• 1
' 1i Y
S\`i\, II •
4 • �1• • J`i. r J•...-r�� ...°%. °rte ,j �1
r> r�N N P` C.`f`� /
Figure 4 South Platte River ed
`-�-�^h�
BASIN MAP
5
961687
WATTENBERG,COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
as the floodplain concept provides a national smaller watersheds contained within the
standard for the National Flood Insurance basins. Flooding results when the flow of
Program (NFIP). water becomes greater than the carrying
capacity of the individual stream channel.
Rate of rise, peak discharge (magnitude),
FLOOD RECURRENCE INTERVALS duration, and frequency of floods, are all a
function of physical features and weather
10-Year Flood Recurrence interval of conditions which contribute to the volume of
about 10 years but a 10% water in the river system. The following
chance of occurring in any describes sources of riverine floods which
year. can effect Wattenberg:
50-Year Flood Recurrence interval of Snow-Melt Floods - Snow-melt flooding
about 50 years but a 2% typically occurs May through June.
chance of occurring in any Generally, this occurs when warm spring
year. temperatures create a fast snow-melt and/or
a combination of spring runoff and rainfall
100-Year Flood Recurrence interval of over the affected watershed. Serious
about 100 years but a 1% flooding can result when heavy spring rain
chance of occurring in any accompanies a snow-melt in May and June.
year.
Flash Floods - These floods result from
intense summer thunderstorms. This flood
500-Year Flood Recurrence interval of event is characterized by an intense
about 500 years but a .2% cloudburst, a sudden rise in stream level.
chance of occurring in any short duration, and almost no warning.
year. Typically, the flash flood season in Colorado
Figure 5 stretches from May through September.
The 100-year floodplain located within the General Rain Floods - These floods are
Community of Wattenberg has been mapped caused by general rainfall events that occur
and is printed in the 1979 Flood Insurance over a wide geographic area for several days,
Study conducted by the Federal Emergency completely saturating the shallow soils.
Management Agency (FEMA) (See Figure These floods are characterized by a slow,
6). It is critical, however, for the floodplain steady rise in the stream level and a peak
residents to remember that floods greater discharge of long duration. The slow rise
than the standard 100-year flood event may rate of the stream provides time for warning.
occur at any time.
Flood History of Wattenberg and
Types of Floods Weld County
Floods occur on riverine systems. As discussed previously, flooding presents a
Commonly, a river basin is fed by a potential problem in Wattenberg and
hierarchical order of stream channels that
convey the normal flow of water from
6
9616 F37
WATTENBERG,COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
WATTENBERG
FLOOD INSURANCE RATE MAP
Weld County Road 6
co
�w c
O O �
Do CO
200� Edward
1100 Meters 1 %�
FredrTh
100- YEAR FLOODPLAIN
liam
Julius
C ' Lupton Bottoms Ditch
iN
Figure 6
7
961.C F.1. 7
W ATTENBERG, COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
throughout Weld County. Historical Denver caused flooding in late May and
analysis is a very important element of flood early June on the South Platte River between
hazard mitigation, as it provides a useful Sand Creek and Fort Lupton. Several
perspective from which to evaluate the flood approaches to county bridges were washed
hazard in Wattenberg and its potential out as well as flooding of some agricultural
impact on the community. It is not intended land. In 1949 heavy rainfall over a melting
to be interpreted as an estimate of exactly snowpack caused flooding on the South
what will occur in the future. Every flood Platte River mid-May to late June from
event is unique. The factors that combine to Littleton, Colorado to North Platte,
create one flood may never occur again. Nebraska. Considerable damage was
Therefore, it is important to be prepared for incurred by homes, farm buildings, and
any combination of factors that may lead to crops along that reach of the river.
a flood event. The following flood accounts
are typical of flood events which have 1965 Flood
occurred along the South Platte River in During the early days of June, each day had
Weld County, but are, by no means, a heavy to torrential rainfall over large
complete history of such. They are portions of the South Platte River basin
presented here to give some insight as to the creating extensive flooding along the South
source and magnitude of floodwaters from Platte River. Heavy rainfall occurred over
the South Platte River. portions of the northern sections of the
South Platte River basin on the 14th and 15th
1921 Flood of June. As the storm system moved
Heavy rainfall over much of the upper South southward, torrential rainfall centered
Platte River Basin caused flooding in Weld principally over Plum Creek, Cherry Creek,
County in early June. Between Brighton and and Sand and Toll Gate Creek watersheds in
Orchard, the wooden bridges were the Denver region, and Bijou Creek, Kiowa
impassable; two were destroyed and the Creek, Comanche Creek, Badger Creek, and
approaches to the others were destroyed for Beaver Creek watersheds to the east.
a distance of several hundred yards (See Extensive flooding occurred on the South
Figure 7). Platte River from Plum Creek downstream
-:r) to North Platte, Nebraska as a result of this
. �-.:1: -"`Y.: rainfall. When it was over, 12 people died
;-is t • and damage was set at $102 million.
Zt �•7��(4Yil� • ' . -
p + I y -X14441-' 1973 Flood
,T �� r to Snowmelt runoff from the lower mountain
t ' - ; t �t y� area of the South Platte River basin began
Eir•yl1R4i (ft- ��Y -a"Y Y -�..�
E. s t =+rr I about the middle of April. On May 5th
c rainfall, amounting to as much as 6 inches,
was the major causative factor of flooding in
the South Platte River basin. Sharp
-r-°� "` increases in the river flow as a result of the
Figure 7 rainfall runoff were recorded at all gauging
1948 and 1949 Floods stations along the South Platte River from
Heavy rainfall over a large area east of Littleton to the Colorado-Nebraska State
8
961687
WATTENBERG,COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
line. Bankfull discharges were experienced PLANNING AND ZONING
along portions of the main stem of the South
Platte River for most of the month of May Weld County Planning Department
and into June.
Weld County's rural areas contain a number
1983 Flood
of small unincorporated residential
It was one of the strangest years for weather
that communities that are surrounding by
Weld County experience. A mild
agricultural uses. Wattenberg is placed into
winter was followed by heavy snows in
this category. Unincorporated communities
April and May. In late May and June, the
generally provide housing for those
mountain stream runoff caused many employed in agricultural and other industries
problems for Weld County. The winter
in the surrounding region.
brought high snowpack levels in the
mountains, and when the early summer With few exceptions, these settlements have
weather became unusually hot, the rivers had little or no growth compared to the rest
began to rise. The area reminded old settlers
of Weld County since their inception.
why the floodplains were there and how they
Substantial population growth is not
were created. The rivers didn't fall below
anticipated in these communities due to the
flood stage until July.
lack of community water and/or sewer
facilities. The goals and policies developed
Large floods can happen in the Wattenberg
by the Weld County Planning Department
area, this was clearly demonstrated by the
for unincorporated Weld County
area floods of 1965. Hazards of large
communities are as follows:
floods, the extent of damage caused by any
flood, depends on the topography of the area
flooded, depth and duration of flooding, Goal 1: Assure proper location and
velocity of flow, rate of rise, developments operation of compatible land uses by
on the floodplain, and the amount of debris maintaining land-use regulations within
in the floodwater. Deep floodwater flowing unincorporated communities.
at high velocity and carrying floating debris
will create conditions hazardous to persons Policy 1: Expansion of existing
and vehicles attempting to cross flooded unincorporated communities will be based
areas. In general, floodwater 3 feet deep or on the following criteria:
more and flowing at a velocity of 3 feet per
second or more can easily sweep an adult Policy 1.1: Urban growth boundary goals
person off his feet, thus creating definite and policies should apply in reviewing land-
danger of injury or drowning. Rapidly rising use applications which are adjacent to or
and swiftly flowing floodwater may trap propose to expand existing unincorporated
persons in homes that are ultimately communities; and
destroyed or in vehicles that are ultimately
submerged or floated. Isolation of areas by Policy 1.2: Additionally, any goals and
floodwaters can create medical, fire, or law policies adopted for a particular type of
enforcement responses. development will also be used for review
and evaluation. For example, the planned
unit development goals and policies would
also apply when reviewing a planned unit
9
9616,57
WATFENBERG, COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
development application adjacent to an Colorado House Bill 1041 (HB-1041)
unincorporated community.
In House Bill 1041, the state acknowledged
Goal 2: Maintain the rural character of that planning in local areas has state wide
these settlements. implications. Local governments are
encouraged to designate specific areas and
Goal 3: Accommodate new development activities that affect the whole state and
primarily through infill of existing vacant manage them in a way that protects interests
plotted lots. of the state. Through this bill funds are
made available to local governments to help
Goal 4: Maintain urban growth boundary them carry out planning.
areas that provide an official definition
between future urban and agricultural land
uses. Weld County Zoning Ordinances
Authority to Plan The Weld County Zoning Ordinances are
written in accordance with the Colorado
State legislation has given local Revised Statutes and apply to all of the
governments in Colorado the power to plan unincorporated territory in Weld County.
their communities and regulate the use of This Zoning Ordinance "is designed to
property. This legislation called "State promote the health, safety, convenience,
Enabling Legislation" outlines specific morals, order, and welfare of the present and
powers that a jurisdiction has to form a future inhabitants of Weld County".
planning commission, and to adopt plans
such as the comprehensive plan and Weld County Zoning Ordinances include a
subdivision regulations. The state section defining Flood Hazard Overlay
legislature has also passed two important Districts. These districts are referred to as
bills since 1970 that restates the authority of Floodway and Floodprone Districts. The
local governments to plan Floodway District includes land which is
within the high hazard area of an
Colorado House Bill 1034 (HB-1034) intermediate regional floodplain. This
includes the channel of a river or other
House Bill 1034 clearly states that local watercourse and the adjacent land areas
governments can: regulate development in required to carry and discharge the largest
hazardous areas, protect land with historic, part of the base flood flow. The Floodprone
architectural and archaeological importance District includes all the land within the
from development, regulate roads on public intermediate regional floodplain which is
lands, regulate the location of activities and outside of the designated Floodway District.
development that may result in significant The Floodprone District is a lower hazard
changes in population density, provide for area which serves primarily as a storage area
phased development of services and for the floodwaters of an intermediate
facilities, regulate the use of land to reduce regional flood. These districts were
impacts on the community or surrounding developed using the Flood insurance Study
areas to ensure planned and orderly use of for Weld Count,y revised September 27,
land, and to protect the environment.
10
961,C437
WATTENBERG, COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
1991, prepared by the Federal Emergency meet the escalating costs of repairing
Management Agency (FEMA). damage to buildings and their contents
caused by floods. Until recently, such
A portion of Wattenberg is zoned as a coverage was generally not available from
Floodprone District. Uses permitted shall private-sector companies.
conform to the underlying zoning permitted
on the community. Uses allowed in the Participation in the NFIP is based on an
underlying zoning district which require a agreement between Weld County and the
building permit shall, in addition, obtain a NFIP. The NFIP requires Weld County to
Flood Hazard Overlay District set up and enforce measures to reduce flood
Development Permit (See Appendix 1 for risks to new construction in special flood
Flood Hazard Development Permit hazard areas. The NFIP will then make
Procedures). flood insurance available within the
unincorporated areas of Weld County as a
Flood Hazard Mitigation financial protection against flood losses.
Activities Flood Insurance Questions &
Answers
Flood Protection Measures To Date
Q: Who may purchase a flood insurance
Currently, there are no flood control olicY°
structures on the South Platte River in the policy?
A: NFIP coverage is available to all and
Wattenberg area, nor is it likely that there occupants of insurable property (a building
will be any future need in Wattenberg for and/or its contents) in Weld County.
costly, large-scale stream containment
projects. To-date, most effective flood Q: How is flood insurance purchased?
hazard mitigation activities in Wattenberg A: A flood insurance policy may be
have involved community participation in purchased from a licensed insurance agent in
the National Flood Insurance Program. Colorado representing the NFIP.
The National Flood Insurance Program Q: Is the purchase of flood insurance
mandatory?
Of the 62,000 structures in the 100-year A: The Flood Disaster Protection Act of
floodplain in Colorado, only 16 percent are 1973, as amended, mandates the purchase of
insured. In unincorporated Wattenberg of flood insurance for FHA, VA and SBA
18 residents surveyed by Kistner and loans secured by a building in the Flood
Associates in the 100-year floodplain only 3 Hazard Area of Weld County. For more
were insured. information contact: Weld County Planning
and Zoning Department, (970) 353-6100,
The National Flood Insurance Program
Ext. 3520.
(NFIP) is a federal program, enabling
property owners to purchase flood insurance
protection against losses from flooding.
This insurance is designed to provide an
insurance alternative to disaster assistance to
11
9616 "1
WATTENBERG, COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
Flood Hazard MitigaitonMeeting past flooding in Wattenberg. Basic flood
hazard mitigation techniques were conveyed
On March 6, 1996 Robert Kistner, of Kistner to residents, and sources for more
and Associates, held a Community Meeting information were supplied.
for Wattenberg to interview residents on
12
967
WATTENBERG,COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
WATTENBERG AND WELD COUNTY FLOOD MITIGATION ACTION
PLAN RECOMMENDATIONS
There are many alternatives to reduce the future impacts of flooding in Wattenberg. These
include structural improvements, emergency preparedness and flood warning, and increased
public awareness. This Hazard Mitigation Plan has been prepared with the intention of offering
concrete, realistic suggestions that the Community of Wattenberg can initiate to help mitigate the
flood hazard. Due to financial constraints, however, some mitigation options contained in this
report will require outside help for funding. Other mitigation alternatives, such as increasing
emergency preparedness and creating a local flood monitoring and warning system will require
support from the Weld County Office of Emergency Management and can be immediately
implemented by the community.
NRecommendation 1. Clean Ditches and Culverts
What: Prior to 1997 flood season, clean ditches, culverts of debris and silt. Develop
annual ditch and culvert maintenance program
Who: Transportation Division, Weld County Department of Public works.
When: During the road maintenance season and before the flood season of February
through July. Maintenance needed yearly.
Supporting Agencies: Weld County Department of Public Works, Weld County Board of
Commissioners.
Recommendation 2. Study if Culverts Need Resizing
What: Study if the increase in culvert size throughout the Wattenberg Community, to
enhance the drainage performance during flood events is needed.
Who: Transportation Division, Weld County Department of Public works.
When: Spring of 1997
Supporting Agencies: Weld County Department of Public Works, Weld County Board of
Commissioners.
13
961€7
WATTENBERG,COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
N Recommendation 3. Floodplain Map Changes
What: Review floodplain Flood Insurance Rate Maps (FIRM) for changes in hydrology
and adjust accordingly.
Who: Weld County Planning and Zoning Department, Colorado Water Conservation
Board and the Federal Emergency Management Agency National Flood Insurance
Program
When: Spring of 1997
Supporting Agencies: Weld County Office of Emergency Management and Weld County
Board of Commissioners.
NRecommendation 4. Deploy Spotter Network
What: Deploy spotter network and new flood emergency plan for local flood detection
and warning (See Appendix 2, Spotter Network).
Who: Wattenberg residents, Weld County Office of Emergency Management, Weld
County Planning and Zoning Department and the Colorado Office of Emergency
Management.
When: Fall of 1996
Supporting Agencies: Weld County Board of Commissioners and the Colorado Water
Conservation Board
Recommendation 5. Conduct Community Hazard Mitigation Workshop
What: Conduct Hazard Mitigation Workshop with Wattenberg Residents on what home
and business owners can do to protect themselves from flood hazards. (See
Appendix 3).
Who: Weld County Office of Emergency Management, and the Colorado Office of
Emergency Management.
When: Fall of 1996
Supporting Agencies: Weld County Board of Commissioners and the Federal Emergency
Management Agency.
14
961.x37
WATTENBERG,COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
APPENDIX 1
Flood Hazard Development Permit Procedure
The purpose of the Flood Hazard Development Permit Application is to give the applicant an
opportunity to demonstrate through written and graphic information how the proposed building
sites, developments and/or structures are safe from flooding if they are to be located within the
Floodprone districts and that the proposal complies with the Weld County Zoning Ordinance, as
amended.
A completed application form and supporting materials will enable the Planning Staff to process
and reach a decision within the time frame established for the Flood Hazard Development Permit
process.
The applicant shall submit the following:
I. A total of three packets of the required Flood Hazard Development Permit application
materials and map ( the original plus two copies);
2. Flood Hazard Development Permit Certification; and
3. Flood Hazard Development Permit application fee.
The Weld County Department of Planning Services shall be responsible for processing a Flood
Hazard Development Permit in the unincorporated areas of Weld County in Accordance with
Section 26.3 of the Weld County Zoning Ordinance, as amended.
15
961(F37
W.ATTENBERG, COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
APPENDIX 2
Spotter Network
One of the most exciting opportunities for flood hazard mitigation in Wattenberg is the
development of a local spotter network for flood warning. This network of volunteers would be
designated to monitor rainfall amounts and the stream level of the South Platte directly affecting
Wattenberg. Rainfall observation stations would monitor local rainfall with standardized rain
gauges so all records could be accurately correlated and compiled into evidence for informed
decision-making by the Weld County Office of Emergency Management.
In this system, daily rainfall records would be kept, but only heavy accumulations would be
relayed to the Weld County Office of Emergency Management, who would calculate the
potential for flood hazard. Rainfall information would be supplemented by stream gauges placed
at strategic points along the South Platte River (See Figure 8).
Stream gauge reports would -`' cSc c r-'' s� ;.e 5
be reported by a designated `• Cj'w i - -
volunteer every time the level r - ' " +4.
changes rapidly or at least z • •:v I y ��•,--..., 3.%
is
every time there is a Ci,-;.',':.
significant change in the -5 1: - ._
stream level (especially as theII •
stream level approaches the ;4, >- : (' ` .It,
designated critical level for 1
;
that site). "Significant" can j-.\ 1_ d
be defined as every increase 1 i All, 0,
r---.—_ - „_rte
of one-quarter to one-half ], 1 / . _
foot in depth: however, over /! '� ,_.: y
time the spotter will be able -
to get a better feel for what _ ,:
kind of changes in the stream -.../. f' A �'
level are significant.
2: 1ii 4
Training provided by the
local Floodplain �. 1
Administrator will also help
define "when" and "what" to r'
report. t
f =
Another important " , 1
component of this spotter a
network is keeping logs. The A 7
process of determining when ` J
a stream is reaching its
critical level is very difficult.
Improved determinations can
16
961.687
WATTENBERG, COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
best come from spotter records. Site-specific records will help determine the "personality" of the
South Platte River. This information will be very useful and should be relayed to the Weld
County Office of Emergency Management, where it can be compiled and analyzed to help better
determine critical levels for the South Platte and to point out areas that seem to have higher
potential danger to human lives and property.
17
961.C n7
WATTENBERG, COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
APPENDIX 3
Floodproofing for Homeowners and Business
Structural modifications (the implementation of mitigation fixtures to buildings or property)offer
numerous mitigation options that are both affordable and simple to construct. Home and
business owners are encouraged to use structural modifications to divert water away from their
premises. Many of the floodproofing techniques that keep water away from a residence, such as
floodwalls, levees, and structural sealing, may require special treatment for openings such as
doors, windows, driveways, etc. These closures act as shields to prevent water from entering,
and can be of a variety of shapes, sizes and materials.
In some cases closures are permanently attached using hinges so that they can remain open when
there is no flood threat. They may be portable, normally stored in a convenient location and
slipped into place when a flood threatens. In certain situations, when flooding is of very low
level, usually less than one foot, some method of enclosing low entrances such as basement doors
or window wells might be a satisfactory option. In any case, there are a number of elements
involved in designing and using a closure system.
In areas of shallow, low velocity flooding, closures can be used on doors, windows, vents. And
other building openings. However, the first step with the use of closures placed directly on
buildings is to be certain that both the closure and the wall systems are strong enough and
sufficiently watertight to withstand flood pressures. The use of closures directly on a structure is
considered to be part of the sealing process (See Figures 9 and 10).
CLOSURE
PANEL
CLOSURE
- i TRACK
IIIII
Figure 9 - Example of a "mini-flood wall" Example 10 - Example of a drop-in closure
Closures can be considered as an option only if a flooding situation provides sufficient time to
install the closures. The need for warning tine and human intervention is critical, since all
closure system require personnel to install them and make certain they are properly sealed.
Closures that are stored between floods must be readily accessible. The effectiveness of an entire
closure system will be compromised if the closures are stored such that flooding renders
18 cc
WATTENBERG,COLORADO FLOOD HAZARD MITIGATION PLAN AucusT 1996
them inaccessible, or one closure is improperly installed.
For cases involving flood levels of up to two feet, a type of "mini-floodwall" can be used to
permanently protect various types of openings. Possible materials for this use include brick,
concrete block and poured concrete. For flooding around basement doors, a low wall around the
entrance may be the solution. Though the "mini-floodwalls" may not require the degree of
reinforcing that larger floodwalls do, they should be supported by and securely tied into a footing •
so that they will not by undercut by scouring.
Sandbagging
As a last resort or during emergencies, sandbags can keep water away from vulnerable property.
However, floodproofing measures and moving contents out the way are much more secure
methods to accomplish the same goal. Additionally, sandbagging can be very expensive.
If your community wants to establish a plan for sandbagging, you will have to buy sandbags
before a flood to be sure you have them on hand. Utilize burlap or plastic sandbags, other types
of bags simply won't hold up. Sand and plastic sheeting must also be stockpiled.
Sandbagging can also be very time consuming. For example, it takes two people approximately
one hour to fill and place 100 sandbags, giving you a wall one foot high and 20 feet long. If you
skimp on the bags, you risk putting up a wall that will be knocked over.
When a flood is imminent, everyone wants to sandbag, usually because they don't know what
else to do. While it does have a therapeutic effect, sandbagging should be considered only as
part of an overall flood response plan, or as a last resort for individuals. A good flood response
plan will help use your limited time and resources most efficiently. Such an overall plan might
call for sandbags, but only as one flood response element. Permanent floodproofing measures
are much more secure methods to accomplish the same thing.
SANDBAGGING STEPS. . ::_
1. Strip the ground of sod._, Grass:gets slippery when wet and your wall,could be pushed along
the ground by the.weight of the water..
2. Dig a bonding trench and lay a plastic sheet in the trench and on the flood side.
3. Fill bags half to three-quarters full. Don't tie them.' . '.:'_:. .` • ::
4. Starting in the bonding trench,lay the bags on top of the plastic sheet. Place each bag on tip
of the pervious one's flap.
5. Lay each layer'S bags at right angles to the layer below it and tamp tightly in place.
6. When you reach your flood protection level, pull the plastic sheet up in front of the wall and
hold it down with more bags
7. If strong current and debris are expected,protect you plastic sheet from ripping with another
layer of sandbags.
19
961€J7
WATTENBERG, COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
APPENDIX 4
In the Event of a Flood: Tips to Minimize Loss of Life and Property
The following are tips that should be used as suggested guidelines for action before, during, and
after a flood.
Steps to Take Today
• Make an itemized list of personal property, including furnishings, clothing and valuables.
This will assist an adjuster settle claims which will prove uninsured losses.
• Learn the safest route from your home to high, safe ground if you have to evacuate in a hurry.
• Keep a portable radio, emergency cooking equipment and flashlights in working order.
• Persons who live in frequently flooded areas should keep on hand materials such as sandbags,
plywood, plastic sheeting, and lumber which can be used to protect private property.
When the Flood Comes
The safety of your family is the most important consideration. Since floodwaters can rise very
rapidly, you should be prepared to evacuate before the water level reaches your property.
• Keep a battery powered radio tuned to a local station, and follow all emergency instructions.
• When caught outside the house, remember, floods are deceptive. Try to avoid flooded areas,
and don't attempt to walk through floodwaters that are more than knee deep.
• If, and only if, time permits there are several precautionary steps that can be taken...
• Turn off all utilities at the main power box. Do not touch any electrical equipment unless it
is in a dry area and you are standing on a piece of dry wood while wearing rubber gloves and
rubber soled boots or shoes. Shut off propane tank valve and leave cover open so fire
department can visually check that tank is shut off.
• Fill bathtubs, sinks and jugs with clean water in case regular supplies are contaminated. You
can sanitize these items by first rinsing with bleach.
After the Flood
If your home, apartment, or business has suffered flood damage, immediately call the agent or
broker who handles your flood insurance policy. The agent will then submit a loss form to the
20
961.€Fi'7
•
WATTENBERG,COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
National Flood Insurance Program. An adjuster will be assigned to inspect your property as soon
as possible.
• Prior to entering a building, check for structural damage. Make sure it is not in danger of
collapsing. Turn off any outside gas lines at the meter or tank, and let the house air for
several minutes to remove foul odors or escaping gas.
• Upon entering the building, do not use open flame as a source of light since gas may still be
trapped inside; a battery-operated flashlight is ideal.
• Watch for electrical shorts or live wires before making certain that the main power switch is
turned off. Do not turn on any lights or appliances until an electrician has checked the system
for short circuits.
• Cover broken windows and holes in the roof or walls to prevent weather damage.
• Proceed with immediate cleanup measures to prevent any health hazards. Perishable items
which pose a health problem should be listed and photographed before discarding. Throw
out fresh food and previously opened medicines that have come into contact with flood
waters.
• Water for drinking and food preparation should be boiled vigorously for ten minutes (until
the public water system has been declared safe). Another method of disinfecting is to mix 1/2
teaspoon of liquid commercial bleach with 2-'/2 gallons of water . . . let stand for five minutes
before using. The flat taste can be removed by pouring the water from one container into
another or adding a pinch of salt. In an emergency, water may be obtained by draining a hot
water tank or melting ice cubes.
• Refrigerators, sofas, and other hard goods should be hosed off and kept for the adjuster's
inspection. A good deodorizer when cleaning kitchen appliances is to add I teaspoon of
baking soda to a quart of water. Any partially damaged items should be dried and aired; the
adjuster will make recommendations as to their repair or disposal. Take pictures of the
damage done to your building and contents.
• Take all wooden furniture outdoors but keep it out of direct sunlight to prevent warping. A
garage or carport is a good place for drying. Remove drawers and other moving parts as soon
as possible, but do not pry open swollen drawers from the front. Instead, remove the backing
and push the drawers out.
• Shovel out mud while it is still moist to give walls a chance to dry. Once plastered walls
have dried, brush off loose dirt. Wash with a mild soap solution and rinse with clean water;
always start at the bottom and work up. Ceilings are done last. Special attention at this early
stage should also be paid to cleaning out the heating and plumbing systems.
21
961.7 1'7
WATTENBERG, COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
• Mildew can be removed from dry wood with a solution of 4 to 6 tablespoons of trisodium
phosphate (TSP), 1 cup liquid chlorine bleach, and 1 gallon water.
• Flooded basements should be drained and cleaned as soon as possible. However, structural
damage can occur by pumping water out too quickly. After the flood waters around your
property have subsided, begin draining the basement in stages, about 1/3 of water volume
each day.
22
961687
WATTENBERG,COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
APPENDIX 5
Sources of Assistance
The following agencies can provide flood assistance before, during, and after a flood:
Weld County Office of Emergency Management
910 Tenth Avenue
Greeley, CO 80631-3873
(970) 356-4015, ext. 4250
Fax: (970) 353-8551
Weld County Planning Services
1400 N. 17th Ave
Greeley, CO 80631
(970) 353-6100, ext. 3540
Fax: (970) 352-6312
Colorado Office of Emergency Management
15075 South Golden Road
Golden, CO 80401-3979
(303) 273-1622
24 Hour Emergency Line (303) 279-8855
Colorado Water Conservation Board
1313 Sherman St, Room 720
Denver, CO 80203
(303) 866-3441
Federal Emergency Management Agency, Region VIII
Building 710
Denver Federal Center
Denver, CO 80225
(303) 235-4800
23
961.697
WATTENBERG,COLORADO FLOOD HAZARD MITIGATION PLAN AUGUST 1996
REFERENCES
Flood Insurance Study, Weld County Colorado Unincorporated Areas and Town of Eaton,
Colorado, Federal Emergency Management Agency, September 27, 1991.
Following a Flood...Steps to Recovery, Federal Emergency Management Agency, November
1990.
Greeley Tribune, May 29, 1995.
Greeley Tribune, May 31, 1995.
Greeley Tribune, June 8, 1995.
Greeley Tribune, June 11, 1995.
Home and Business Guide for the Mitigation of Flooded Basements, Division of Local
Government, Divsion of Local Affairs and Colorado Office of Emergency Management,
1993.
Special Flood Hazard Information Report. South Platte River, Weld County, Colorado,
Department of the Army, Omaha District, Corps of Engineers, April 1977.
Weld County, Colorado Comprehensive Plan, Weld County Department of Planning Services,
November 21, 1995.
Weld County, Colorado Zoning Ordinance, Weld County Department of Planning Services,
October 31, 1995.
Contacts:
Ed Herring - Weld County Office of Emergency Management
Weld County Commissioners
Tony Alatore-Wattenberg Resident
Weld County Department of Planning Services
Larry Lang- Colorado Water Conservation Board
24
916/1387
Hello