TOWN OF OLIVE LOCAL FLOOD ANALYSIS APPENDIX C:...

TOWN OF OLIVE LOCAL FLOOD ANALYSIS

APPENDIX C: TOWN-WIDE FLOOD HAZARD MITIGATION PLAN

TOWN OF OLIVE ULSTER COUNTY, NEW YORK

Prepared for:

Town of Olive

45 Watson Hollow Road West Shokan, NY 12494

In partnership with:

Cornell Cooperative Extension of Ulster County 3130 Route 28 Shokan, NY 12481

Prepared by:

Shumaker Consulting Engineering and Land Surveying, DPC 143 Court Street Binghamton, New York 13901

February 13, 2019

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1.0 Introduction

Background The Town of Olive (Town) has been subject to numerous flooding events in its recent history, the worst of which at the time of this report was Hurricane Irene in August 2011. During Hurricane Irene, record flooding was recorded on Esopus Creek and the Bushkill and there was widespread flooding of residences and businesses throughout the town, forcing many residents to find temporary shelter. Where flooding caused damage to businesses, access to basic necessities was restricted even for those residents that were not directly impacted by the flood. Overtopping of undersized stream crossings caused the temporary closure of local, county, and State roads that limited evacuation routes for residents and access for emergency responders. In addition, streambank erosion beyond natural rates during these flood events caused the sudden loss of property. This streambank erosion as well as the introduction of pollutants from flooded houses impacted downstream water quality and drinking water supplies (Ulster County New York Rising Community Reconstruction Planning Committee [Ulster NYRCRP Committee), 2014).

While the flooding from Hurricane Irene was devastating to the Town and communities across New York, it did provide the benefit of increasing community awareness of the natural hazards posed by streams and re-focused municipal efforts to prepare for and proactively mitigate future flood damage. Since Hurricane Irene, the Town, Ulster County, the State, the Ashokan Watershed Stream Management Program (AWSMP), and others have worked to identify existing flood hazards and potential policy, preparation, prevention, and response actions to mitigate future flood impacts. Examples of these efforts include the following reports:

• New York Rising Community Reconstruction Plan for Ulster Communities (Ulster NYRCRP Committee, 2014);

• Bush Kill Stream Management Plan (Ulster County Soil and Water Conservation District, 2015);

• Flood Insurance Study, Ulster County, New York (All Jurisdictions) (FEMA, 2016)

• Multi-Jurisdictional Hazard Mitigation Plan for Ulster County, NY (MJHMP; Ulster County Department of Emergency Communications/Emergency Management, 2017); and,

• Local Flood Analysis for the Hamlets of Boiceville and West Shokan (Boiceville and West Shokan LFA; Cornell Cooperative Extension of Ulster County, 2017).

• Maltby Hollow Brook Stream Feature Inventory and Management Recommendations (Maltby Hollow SFI; AWSMP, 2018)

Study Purpose The Cornell Cooperative Extension of Ulster County and the Town have procured Shumaker Consulting Engineering and Land Surveying, DPC (Shumaker) to prepare this Town-wide Flood Hazard Mitigation Plan (Plan) to supplement the MJHMP and extend the Boiceville and West Shokan LFA (Cornell Cooperative Extension of Ulster County, 2017) to include the entirety of the Town. Figure 1 provides a map of the Town, the New York City watershed boundary, and mapped floodplains within the Town. Within the Town limits and outside of the hamlets of Boiceville and West Shokan, the intent of the Plan is to consolidate work completed in previous studies and advance those efforts to develop a prioritized, actionable plan to implement individual projects and programs to reduce flood risk across the Town.

Study Funding The development of the Plan was funded in part by a grant from the Hudson River Valley Greenway. The remainder of the funding for the Plan was provided by the Cornell Cooperative Extension of Ulster County.

Town of Olive

Town of Woodstock

Town of Shandaken

Town of RochesterTown of Marbletown

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contributors, and the GIS user community

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Town-wide Flood Hazard Mitigation Plan

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December 2018

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Town of Olive - Flood Hazard Location Overview Map

FIGURE 2A

Shumaker Consulting Engineering and Land Surveying, DPC

143 Court Street

Binghamton, NY 13901

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2.0 Progress Towards Mitigating Flood Hazards Since preparation of the studies identified in Section 1, Background, the Town, Ulster County, AWSMP, and other local partners have completed, or are intending to complete in the next year, several projects to mitigate flood hazards within the Town limits. Table 1 summarizes the flood mitigation activities that have been completed since Hurricane Irene in 2011. Shumaker recommends that the Town maintain this list of completed projects and update it when additional projects are completed. Should the Town elect to participate in the Community Rating System (discussed in detail in Section 5, Additional Actions to Mitigate Flood Hazards), this list of projects could potentially be used by the Town to achieve credit towards a higher Community rating classification.

3.0 Flood Hazard Identification and Risk Assessment

Flood Hazard Identification As part of the Plan, Shumaker reviewed the previous studies identified in Section 1, Background and consolidated the identified flood hazards (outside of the Boiceville and West Shokan hamlet areas) into a single, consolidated list and map provided as Table 2 and Figure 2, respectively. One exception was the Maltby Hollow Stream Feature Inventory and Management Recommendations – as this study was focused on identifying stream features at a detailed level and providing limited reach-scale recommendations, the report was referenced only for supporting detail for flood hazards identified by other means. Shumaker then added additional flood hazards to this consolidated list that were identified by members of the Town of Olive Flood Advisory Committee (FAC) as well as the general public in a “push-pin” exercise where known hazards were identified by members of the FAC on a map of the Town. This FAC was composed of members of the general public, the Town, and the County that was supported by technical advisors from the New York City Department of Environmental Protection, AWSMP, and the Catskill Watershed Corporation. Each flood hazard was identified as one of the following types of flood hazards defined in the Boiceville and West Shokan LFA:

• Riverine Flood Hazard - A location where overflow from a river, stream, or creek damages assets and often results in a federal disaster declaration. This type of flooding generally occurs more than six hours after peak rainfall.

• Flash Flood Hazard - A location where a rapid and extreme flow of high water overflows from a river, stream, or creek channel into a normally dry area beginning within six hours of an intense rainfall event. Ongoing flooding can intensify to flash flooding in cases where intense rainfall results in a rapid surge of rising flood waters, i.e. a minor flooding event rapidly becomes a larger flooding event after another burst of intense rain.

• Stormwater Flood Hazard - A location where damage to assets occurs resulting from insufficient capacity of private or municipal stormwater drainage infrastructure. This includes ditches, catch basins, and piping systems.

• Debris Jam Flood Hazard - A location where damage to assets occurs resulting from flooding or erosion that is caused by debris reducing the capacity of water corridors, bridges, culverts, or stormwater drainage infrastructure. Debris can be wood, bedload (i.e., river sediment moved by water in streams), or manmade (e.g., sofas, car parts).

• Erosion Hazard - Eroding banks that threaten public or private infrastructure. Threatened infrastructure is near an actively eroding bank (notable movement of bank over the last five years) and the rate of erosion could threaten infrastructure within the next five years.

• Ice-Jam Flood Hazard - A location where damage to assets occur resulting from flooding or erosion caused by ice jams. An ice jam is an accumulation of ice that acts as a natural dam and restricts flow of a body of water. Ice jams may build up to a thickness great enough to raise the water level and cause flooding.

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Table 1: Summary of Completed or Planned Flood Hazard Mitigation Projects Project Name Location Description Project Owner Status

Streambank Stabilization Bushkill Stabilization of streambank on the Bushkill that was threatening private property

Private landowners and/or Ulster County

Completed 2012

Mine Hollow Culvert Replacement Bushkill Replacement of two CMP culverts with larger precast box culvert to better convey flow and sediment.

Ulster County Department of Public Works

Completed 2016

Maltby Hollow Streambank Stabilization Maltby Hollow

Stabilization of eroded streambank along Maltby Hollow and Moonhaw Road, near Shultis Road. Note that stabilization is limited in scope and additional work is recommended in this reach as part of the Maltby Hollow SFI (AWSWMP, 2018).


Ongoing

Hanover Meadows Bridge Debris Removal

Maltby Hollow

Removal of debris accumulated on Hanover Meadows Bridge across Maltby Hollow. On-going debris removal will be required. Additional work is recommended in this reach as part of the Maltby Hollow SFI.

Private landowners Ongoing

Maintenance

County Road 42 Reconstruction and Streambank Stabilization

Bushkill

MJHMP (2017) Action #28 – Stabilization of streambank erosion and hillslope failure. Re-establishment of two-way traffic on road that was restricted to one-way traffic due to erosion-induced loss of roadway.


Completed 2018

Daylighting of Old Route 28 culvert over Unnamed Tributary

Boiceville Replacement of stream crossing to reduce frequency of State Route 28 overtopping

Town of Olive Design 2019

Replacement of DeSilva Road culvert over Unnamed Tributary

Boiceville Replacement of stream crossing to reduce frequency of DeSilva Road overtopping


Replacement of Upper Boiceville Road bridge over Unnamed Tributary

Boiceville

Flood Resiliency Strategy #3 from Boiceville and West Shokan LFA to replace potentially undersized stream crossing to maintain accessibility across this critical road that is an alternate access when State Route 28 is closed due to flooding.


Replacement of County Road 4 Bridge over Tongore Brook

Olivebridge MJHMP (2017) Action #23 - Replacement of bridge crossing. Anticipated to reduce flood damage to bridge and nearby private property.


Design 2019; Construction

2020

Replacement of Burgher Road culvert over Dry Brook

West Shokan

Flood Resiliency Strategy #5 from Boiceville and West Shokan LFA to replace potentially undersized stream crossing to maintain access to residences that would otherwise be isolated if the crossing were to fail.


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Table 2: Summary of Identified Flood Hazards and Risks

ID Location Hazard Type Description Ownership Probability Impact Spatial Extent

Warning Time

Duration Quantified

Ranking Qualified Ranking

In MJHMP? In

SCMP? Comments **

1 Samsonville Flash Flood Potentially under-sized Upper Samsonville Road crossing across Mettacahonts Stream.

Town 2 2 1 3 1 1.8 Low No No

2 Samsonville Flash Flood Potentially under-sized private crossing across Mettacahonts Stream. Potential flood hazard

Private 2 1 1 3 1 1.5 Low No No

3 Samsonville Flash Flood Potentially under-sized CR 3 crossing across Mettacahonts Stream. In poor condition; may be lost in flood.

County 2 3 2 3 1 2.3 Low Yes,

Action #24 No

Medium priority per MJHMP

4 Samsonville Flash Flood

Two potentially under-sized culverts which may cause regular inundation of Jomar Lane. One culvert is near-blocked with debris. Raising the road to mitigate overtopping may exacerbate Flood Hazard #5.

Town 3 2 1 3 1 2.1 Low Yes,

Action #7 No

High priority per MJHMP; priority because of proximity to #5

5 Samsonville Flash Flood Regular inundation of 750 feet of County Road 3 that prevents traffic and disconnects emergency services.

County 3 3 2 3 1 2.6 Moderate Yes,

Action #26 No


6 Samsonville Flash Flood Potentially under-sized culvert beneath Brown Road Town 2 2 1 3 1 1.8 Low No No

7 Krumville Flash Flood Potentially under-sized crossing of Sahler Mill Road across Beaver Dam Creek causes frequent road overtopping

Town 2 2 1 3 1 1.8 Low Yes,

Action #8 No

High priority per MJHMP

8 Krumville Flash Flood Potentially under-sized crossing of Brown Road over Rochester Creek unable to handle flood discharges

Town 2 2 1 3 1 1.8 Low Yes,

Action #9 No


9 Brodhead Flash Flood Two under-sized crossings of High Point Mountain Road over stream (Pencil Brook?) near Bitterman Road

Town 2 2 1 3 1 1.8 Low No No Anticipated 2020

10 Brodhead Flash Flood Four potentially under-sized crossings of Brodhead Road over stream (Pencil Brook?) between McMillian Road and High Point Mountain Road

Town 2 2 1 3 1 1.8 Low No No

11 Brodhead Flash Flood Two potentially under-sized crossing of McMillian Road over stream (Pencil Brook?)

Town 2 1 1 3 1 1.5 Low No No

12 Shokan Debris Jam

Undersized crossing of Butternut Stream at Red Maple Road has filled in with sediment, woody debris, and possibly ice which contributes to flooding, including flooding of nearby private residence in 1980s.

Town 3 3 2 3 1 2.6 Moderate Yes,

Action #12 No


13 Shokan Flash Flood / Debris Jam

Butternut Stream at Bostock Road has filled in with sediment and accumulation of woody debris; parts of culvert are completely corroded; culvert is undersized.

Town 2 3 4 3 1 2.7 Moderate Yes,

Action #19 No


14 Maltby Hollow Debris Jam Debris jam, possibly causing Flood Hazard #15 N/A 3 2 1 3 1 2.1 Low Yes,

Action #15 No


15 Maltby Hollow Flash Flood Repetitive loss property along Moonhaw Road Private 2 2 1 3 1 1.8 Low No No

16 Maltby Hollow Debris Jam Large woody debris accumulation near Hanover Meadows Bridge potentially contributing to flooding

Private 3 2 1 3 1 2.1 Low Yes,

Action #15 No


17 Maltby Hollow Debris Jam Large woody debris accumulation potentially contributing to flooding

N/A 3 2 1 3 1 2.1 Low Yes,

Action #15 No


18 Maltby Hollow Debris Jam Unstable channel and sedimentation contributing to streambank erosion

N/A 3 2 1 3 1 2.1 Low Yes,

Action #15 No


19 Maltby Hollow Debris Jam Unstable channel upstream of CR 42 N/A 3 2 1 3 1 2.1 Low Yes,

Action #15 No


20 Every Road Erosion Unstable hillslopes and streambank erosion; presence of clays in hillslope is a water quality concern that may justify DEP action to uphold filtration avoidance

Town 3 2 1 3 1 2.1 Low No No

21 Every Road * Flash Flood Undersized County Road 42 crossing has accumulated debris and may lead to inundation of CR 42 during flood events

County 3 3 2 3 1 2.6 Moderate No No

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ID Location Hazard Type Description Ownership Probability Impact Spatial Extent

Warning Time

Duration Quantified

Ranking Qualified Ranking

In MJHMP? In

SCMP? Comments **

22 Every Road * Debris Jam Culverted ford crossing of tributary has filled in with sediment

Private 3 1 1 3 1 1.8 Low No Yes Low priority per SCMP

23 Bushkill * Erosion Leaning sheetpile wall with perched culvert from adjacent tributary. Opposite bank is eroding with evidence of hillslope failure.

County 2 3 2 3 1 2.3 Low Yes,

Action #28 Yes

Critical priority per SCMP; high priority per MJHMP

24 Bushkill * Erosion Erosion along abutments of New York State Department of Environmental Conservation pedestrian bridge crossing

State 2 1 1 3 1 1.5 Low No Yes High priority per SCMP

25 Bushkill * Erosion Continued streambank erosion and hillslope collapse threatens CR 42.

County 3 3 2 3 1 2.6 Moderate Yes, Action

#28 Yes

Critical (SCMP) and high (MJHMP) priority

26 Bushkill * Debris Jam Sediment aggradation from Winchell Brook has nearly filled in culvert beneath CR 42; sediment berms from past debris indicate this is a recurring problem.

County 3 3 2 3 1 2.6 Moderate Yes,

Action #28 Yes


27 Bushkill * Erosion Scour beneath dry-stacked stone wall threatens streambank and CR 42

County 2 3 2 3 1 2.3 Low No Yes Medium priority per SCMP

28 Bushkill * Erosion Scour along streambank threatens CR 42 Private / County 2 3 2 3 1 2.3 Low No Yes Low priority per SCMP

29 Bushkill * Debris Jam Debris jam along meander may be exacerbating erosion of streambank

Private / County 3 3 2 3 1 2.6 Moderate No Yes Low priority per SCMP

30 Bushkill * Erosion Streambank erosion and failed hillslope Private / County 2 3 2 3 1 2.3 Low Yes,

Action #28 Yes


31 Bushkill * Erosion Streambank threatens CR 42; some loss of riprap already Private / County 2 3 2 3 1 2.3 Low No Yes Low priority per SCMP

32 Bushkill * Erosion Streambank erosion adjacent to South Hollow Road bridge

Town / County 2 2 1 3 1 1.8 Low No Yes High priority per SCMP

33 Bushkill * Flash Flood Private bridge crossing of Bushkill Private 2 1 1 3 1 1.5 Low No No

34 Bushkill * Flash Flood Private bridge crossing of Bushkill; Flood Insurance Study shows several feet of rise as the result of private crossing that may affect upstream residences

Private 3 3 1 3 1 2.4 Moderate No Yes High priority per SCMP

35 Bushkill * Debris Jam Woody debris jam observed upstream of Maltby Hollow confluence

Private / Town 3 2 2 3 1 2.3 Low No No

36 West Shokan Groundwater Repetitive loss property near Moonhaw Road and CR 42 Private 2 2 1 3 1 1.8 Low No No

37 West Shokan Groundwater Repetitive loss property along SR 28A Private 2 2 1 3 1 1.8 Low No No

38 Town-wide Communication Lack of emergency notification system to alert residents via e-mail, phone, etc., of impending floods or other natural hazards.

Town or County 4 4 4 3 4 3.9 High Yes, Action

#18 No


* See appropriate Stream Management Plans for more specific locations ** A different prioritization scheme was used for the SCMP that also considers stream function and water quality. In addition, the SCMP and the Town’s appendix to the MJHMP are limited in geographic scope to the Bushkill and the Town, respectively, whereas the TWFHMP adopted the prioritization scheme that was developed for the county-wide MJHMP. In other words, a high priority action in a particular area may become a low or moderate priority if it is re-considered against more actions over a larger area. Note: Highlighted cells identify flood hazards that are priorities for mitigation.

Map Insert: See Enlargementfor Bushkill Hazards

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• High Groundwater Flood Hazard - An area where damage occurs in areas not connected to recognizable drainage channels. Such flooding generally occurs from elevated groundwater from nearby riverine flooding or the accumulation of surface runoff in concave basins.

• Unknown Flooding Hazard - The cause of flooding is not known.

After consolidating additional flood hazards nominated by the FAC into previously-identified flood hazards, Shumaker then updated this list of flood hazards by removing those flood hazards which had been mitigated by recent flood mitigation actions summarized in Table 1. However, flood hazards that had been recently mitigated but had a moderate risk of reoccurrence were retained on the list of identified Flood Hazards provided as Table 2. Examples of such flood hazards include debris accumulated on the Hanover Meadows Bridge – although debris accumulated during Hurricane Irene was removed from the bridge, accumulation of debris on this bridge during future storms remains a moderate possibility.

Although not specifically identified as such, it should be noted that many flood hazards and every flood-prone property are also potential water quality hazards; flooding of a private property could cause contamination of downstream waters if household chemicals, debris, fuel tanks, or other sources of pollutants are damaged or otherwise washed downstream. Similarly, streambank erosion may introduce fine sediments or manmade materials into a receiving stream that impairs downstream water quality. Therefore, many of the flood hazards identified in Table 2 may also be water quality hazards which could provide access to additional funding sources to mitigate such hazards.

Hazard Ranking After identifying the current flood hazards in Table 2, Shumaker assigned a hazard ranking to each flood hazard to support the prioritization of flood mitigation actions. For the ranking of these flood hazards, Shumaker adopted the same criteria as used in the MJHMP. Adopting this methodology provides the following advantages to this Plan:

• The MJHMP hazard ranking methodology has been previously vetted for use in prioritizing natural and anthropogenic hazards in Ulster County;

• Aggregates qualitative assessments of each hazard’s probability of occurrence, impact, spatial extent, warning time, and duration;

• The methodology is consistent with the MJHMP and provides the Town the option to use this Plan as a resource to prioritize hazard mitigation projects within the Town in future updates of the MJHMP; and,

• Is consistent with FEMA’s Local Mitigation Planning Handbook (2013)

The hazard ranking methodology used in the MJHMP assigns one to four points to each of the following five categories: probability (of occurrence), impact, spatial extent, warning time, and duration. The qualitative descriptions for each of the four scores assigned to the five categories per the MJHMP are summarized in Table 3 (on the following page).

The assigned values of each of these five categories are then weighted to generate a single hazard ranking score. The weighting formula used in the MJHMP and adopted by the Plan is as follows:

Hazard Ranking = (0.3 x Probability) + (0.3 x Impact) + (0.2 x Spatial Extent) +

(0.1 x Duration) + (0.1 x Warning Time)

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Qualitative rankings of high, moderate, and low are then assigned based on the following quantified hazard rankings:

• High Hazard Ranking: Hazard ranking equal to or greater than 3.0

• Moderate Hazard Ranking: Hazard Ranking between 2.4 and 2.9

• Low Hazard Ranking: Hazard Ranking equal to or less than 2.3

Table 3: Hazard Ranking Criteria Ranking Category

Level Criteria Index Value

Weighting Factor

Probability

Unlikely Less than 1% annual probability. 1

30% Possible Between 1% and 10% annual probability. 2

Likely Between 10% and 100% annual probability. 3

Highly Likely 100% annual probability. 4

Impact

Minor Very few injuries, if any. Only minor property damage and minimal disruption on quality of life. Temporary shutdown of critical facilities.

1

30%

Limited Minor injuries only. More than 10% of property in affected area damaged or destroyed. Complete shutdown of critical facilities for more than one day.

2

Critical

Multiple deaths/injuries possible. More than 25% of property in affected areas damaged or destroyed. Complete shutdown of critical facilities for more than one day.

3

Catastrophic

High number of deaths/injuries possible. More than 50% of property in affected area damaged or destroyed. Complete shutdown of critical facilities for 30 days or more.

4

Spatial Extent

Negligible Less than 1% of area affected. 1

20% Small Between 1% and 10% of area affected. 2

Moderate Between 10% and 50% of area affected. 3

Large Greater than 50% of area affected. 4

Warning Time

> 24 hours Self-explanatory. 1

10% 12 to 14 hours Self-explanatory. 2

6 to 12 hours Self-explanatory. 3

< 6 hours Self-explanatory. 4

Duration

< 6 hours Self-explanatory. 1

10% 6 to 24 hours Self-explanatory. 2

1 day to 1 week Self-explanatory. 3

> 1 week Self-explanatory. 4

The assigned scores for each ranking category and both the quantified and qualified hazard ranking for each of the flood hazards have been summarized in Table 2 alongside each flood hazard. Only one flood hazard was ranked as a high hazard. Of the remaining hazards, eight were ranked as moderate hazards and the remaining 29 were ranked as low hazards. While several flood hazards were ranked as “low hazard”, it is important to note this is a relative scale – in relation to other flood hazards, these are low hazards, but on an absolute scale they are likely significant hazards that justify action.

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4.0 Town-wide Flood Hazard Mitigation Plan

Selection of Priority Flood Hazards for Mitigation After assigning a hazard ranking to each flood hazard, flood hazards were prioritized for mitigation in coordination with the FAC during a meeting held on September 20, 2018. In general, flood hazards prioritized for mitigation were selected as those flood hazards in Table 2 with the highest hazard ranking or those flood hazards that are known to be most imminent (e.g., flooding of Repetitive Loss Properties is expected in the future if no mitigation is undertaken). However, one flood hazard with a lower hazard ranking was recommended by the FAC for prioritization based on its proximity and potential contribution to higher-ranked flood hazards. Flood hazards identified for priority mitigation are identified by the orange rows in Table 2 and are summarized below:

1. Lack of an emergency notification system (Flood Hazard 38) 2. Various undersized stream crossings (Flood Hazards 4, 5, 12, 13, 21, and 26) 3. Undersized private stream crossings throughout Town 4. Repetitive Loss Properties throughout Town

Rationale for the selection of each of these alternatives and conceptual mitigation actions are provided in the following sub-sections.

Lack of an Emergency Notification System Rationale for Selection: The lack of an emergency notification system was identified as the highest-ranking flood hazard within the Town of Olive as the lack of a system affects every resident and business in Town. If an emergency notification system were implemented, it could be used to reduce the loss of life, injuries, and property damage across the entirety of the Town for both flood and non-flood hazards by notifying residents in a specific area (or the whole Town) of an impending hazard. This early notification can provide residents the advance notice to evacuate to a safe location, protect their properties, and/or relocate flood-prone belongings to areas of their property at lower risk of flooding. In addition, an emergency notification system can also be used to alert residents of alternate evacuation routes when flooding or other hazards prevent the safe use of particular Town, County, or State roads.

Conceptual Mitigation: Several commercial emergency notification systems exist that use a combination of phone calls, e-mails, texts, and other media to communicate emergency notifications. However, as Ulster County is currently in the process of implementing a County-wide community emergency notification system via EverBridge®, Shumaker and the FAC recommend that the Town convey its support for the near-term implementation of this system to the County. Upon implementation of the emergency notification system, the Town should work with the County to re-train at least two Town staff in the use of the system to issue targeted alerts for pending flood hazards and other threatening situations within the Town. In addition, after implementation, the Town should educate residents on the benefits of this system and encourage residents to enroll in notifications.

Repetitive Loss Properties Rationale for Selection: A Repetitive Loss Property (RL) is defined by FEMA as any insurable building for which two or more claims of $1,000 were paid by the National Flood Insurance Program in any rolling 10-year period (FEMA, 2018). Three such properties meeting this definition exist within the Town. By definition, these properties are particularly prone to damage from flooding. As the Federal government reimburses eligible costs for repair of flood damage to the owners through the NFIP, reducing damage to RL properties is a priority for FEMA to reduce or avoid future flood damage claims by reducing or avoiding the flood damage to begin with. In addition, loss of life or injuries are also anticipated to be more likely at RL properties such that mitigating flood risk at RL properties is also anticipated to mitigate the risk of future loss of life or injury.

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Conceptual Mitigation: Shumaker and the FAC recommend that the Town pursue opportunities to reduce the flood risk to RL properties within the Town. Several mitigation options are available to mitigate the risk to RL properties, including the following:

• Acquisition of the property, including outright purchase and removal of the property;

• Re-location of the property to a less flood-prone location;

• Elevation of the inhabitable space of a structure to a higher elevation; and,

• Dry flood-proofing of the structure to prevent water access into the structure during floods.

Several funding sources are available to reduce the flood risk to RL properties and many require the applicant to be a public entity. Therefore, it is recommended that the Town engage the owners of RPL properties and identify their interest in the mitigation options identified above. Where a resident has expressed interest, it is recommended that the Town act on behalf of the resident to apply for mitigation funding via FEMA’s Repetitive Loss Claims Grant, the Catskill Watershed Corporation’s Flood Hazard Mitigation Implementation Program, or the New York City-Funded Flood Buyout Program. Details for these funding programs are provided in Appendix D.

Undersized Public Stream Crossings Rationale for Selection: All of the stream crossings identified as flood hazards have been noted to be potentially undersized based on multiple previous overtoppings of the crossing and/or the size of the crossing in relation to the stream dimensions the crossing conveys. In addition to increasing the risk of damage as the result of overtopping, such crossings are a further flood risk as the overtopping of these crossings restrict evacuation routes and emergency responders, increase the risk of death or injury by presenting an opportunity to ford the overtopped crossing, increase upstream water surface elevations which may affect occupied structures, and create hydraulic conditions that are more prone to the deposition of sediments upstream of the crossing and scour and erosion downstream of the crossing. In addition, the following unique characteristics were identified for the crossings identified as priority projects:

• Bostock Road across Butternut Creek: This local road is the shortest path between the Town Police Department and State Route 28; if this crossing were lost during a flood, emergency responders would have to travel an additional 1.1 miles through a residential area to access State Route 28, reducing the response time to most of the Town. The current crossing also exhibits signs of corrosion which reduces its structural integrity. There are also occupied structures upstream that may have reduced flood risk if the crossing were improved.

• Red Maple Road across Butternut Creek: In the event that Bostock Road cannot be crossed, this would be the alternate route for the Town police to access State Route 28. However, this crossing is also potentially undersized and could be overtopped and inaccessible during a similar-sized event as overtops Bostock Road. If both crossings were impassable, emergency responders would have to travel an additional 6.5 miles through a residential area to access State Route 28 east of Bostock Road, reducing the response time to portions of the Town of Olive. In addition, there are also structures upstream that may have reduced flood risk if the crossing were improved.

• County Road 42 across Every Brook: This crossing appears to be undersized and prone to clogging with woody debris; overtopping could cause the closure and/or loss of County Road 42, a primary travel way from Olive to the Town of Denning and the only means of emergency access from Town facilities in West Shokan to numerous residences along the Bushkill. If County Road 42 were impassable, emergency response would need to be coordinated through the Town of Denning and/or Olive responders would be detoured approximately 40 miles.

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• County Road 42 across Winchell Brook: This crossing is prone to clogging with sediment as evidenced by numerous sediment debris piles adjacent to the culvert crossing; continued sediment aggradation would increase the frequency the crossing is overtopped and could cause the closure and/or loss of County Road 42, a primary travel way from Olive to the Town of Denning and the only means of emergency access from Town facilities in West Shokan to a few residences upstream of Winchell Brook along the Bushkill. If County Road 42 were impassable, emergency response would need to be coordinated through the Town of Denning and/or Olive responders would be detoured approximately 40 miles.

• County Road 3 across Unnamed Tributary (near Jomar Lane): This crossing has been noted to overtop and inundate several hundred feet of County Road 3, a primary travel route across the Town of Olive, on a regular basis. Two culverts downstream of the site, near Jomar Lane, may also contribute to overtopping of this crossing.

• High Point Mountain Road across Unnamed Tributary: Two stream crossings along High Point Mountain Road, an alternate access route between West Shokan and County Road 3, are planned to be replaced by the Town in 2020 and recommended by the FAC to be prioritized.

Conceptual Mitigation: Shumaker recommends these crossings be replaced with a larger structure that spans the bankfull channel and meets stream crossing guidelines established by the New York State Department of Environmental Conservation. These guidelines can be accessed at the following link:

https://www.dec.ny.gov/permits/49060.html

In addition to improving the conveyance capacity of the stream crossing and decreasing upstream flood risk, stream crossings designed to meet these requirements are generally more resilient to flooding (i.e., require fewer repairs and less frequent replacements due to flooding); less prone to overtopping, erosion, scour, and upstream sediment deposition; and improve conditions for migration of aquatic organisms including trout. For additional information on the benefits of properly-sized stream crossings, the following white paper documents the superior performance, and the resulting cost savings, of properly-sized crossings in comparison to traditionally-sized crossings in Vermont during Hurricane Irene:

http://www.maineaudubon.org/wp-content/uploads/2017/09/Roads_Floods_Economics-Gillespie-et-al-2014.pdf

To support the Town with the planning and prioritization of these culvert replacements, Shumaker performed limited hydrologic and hydraulic analyses of the existing stream crossings to quantify the overtopping frequency of the culverts and preliminary dimensions for a replacement culvert. Shumaker also developed planning-level cost estimates for each proposed replacement culvert. It is important to note that these analyses are preliminary and that detailed survey, hydraulic analysis, and engineering considerations will need to be performed to fully consider site topography, culvert alignments, culvert geometry, traffic needs, and structural design of the crossings. The following bullets summarize the methodology and simplifying assumptions Shumaker used to assess the overtopping frequency of the existing culverts:

• Hydrology was developed using the SCS TR-20 runoff methodology embedded within HydroCAD®, version 10.00 with the following inputs:

o StreamStats was used to determine the contributing drainage area to the crossing o The USGS National Landcover Database and Ulster County Soil Survey mapping were

used to quantify a single, weighted curve number for the watershed o The Folmar-Miller Lag equation was used to estimate basin lag time

https://www.dec.ny.gov/permits/49060.html



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o NOAA Atlas 14 rainfall estimates were used for design rainfall depths

• Overtopping frequency were quantified using HydroCAD® and the following inputs: o Free-discharge conditions (no downstream backwater reducing the capacity of the

culvert crossing) were assumed for all stream crossings o The geometry of existing stream crossings was determined from culvert assessment

data collected by the AWSMP except for the County Road 3 and the nearby Jomar Lane crossings, which were field measured by Shumaker staff

o Ulster County 2-ft LiDAR contour data to identify the elevation of the road crossing which was then used to “raise” the relative elevations of the culvert collected in the field to the North American Vertical Datum of 1988

The overtopping frequencies of the existing crossings determined from this hydraulic modeling are summarized in Table 4. In general, the existing crossings are anticipated to overtop the roadway from discharges with an annual chance exceedance (ACE) between a 20 percent (5-year recurrence interval) and 4 percent (25-year recurrence interval). Even without accounting for climate change, several of these culverts do not meet New York State Department of Transportation (NYSDOT) minimum requirements of conveying the 10 percent ACE (10-year recurrence interval) discharge for culverts (crossings less than 20 feet in width) or the 2 percent ACE discharge (50-year event) for bridges (crossings greater than 20 feet in width).

Table 4: Culvert Analysis Summary

Crossing

Existing Proposed EOPCC (Range)

Size (w*h)

Overtopping Frequency

Size (w*h)

Overtopping Frequency

Bostock Rd over Butternut Creek

CMP Elliptical 85x54

< 4.0% ACE RCP Box 384x72

> 0.1% ACE $503,000

($302,000 to $755,000)

Red Maple Dr over Butternut Creek


< 10% ACE RCP Box 360x78

> 0.1% ACE $417,000

($250,000 to $626,000)

County Rd 42 over Every Brook



> 0.2% ACE $307,000

($184,000 to $461,000)

County Rd 42 over Winchell Brook



> 0.5% ACE $276,000

($166,000 to $414,000)

County Rd 3 over Unnamed Tributary

Steel Round 36” diameter

< 50% ACE RCP Box 210x48 *

~ 2% ACE $451,000

($271,000 to $677,000)

High Point Mountain Rd over Unnamed Tributary (North)

CMP Round 47x40

> 0.2% ACE RCP Box 228x54

> 0.1% ACE $324,000

($194,000 to $486,000)

High Point Mountain Rd over Unnamed Tributary (South)

CMP Arch 96x46

< 4.0% ACE RCP Box 216x60

> 2% ACE $291,000

($175,000 to $437,000)

* Raising the profile of approximately 850 feet of County Road 3 approximately one foot is also recommended.

The following bullets summarize the simplifying assumptions Shumaker used to determine a preliminary size of the replacement culverts:

• Hydrologic estimates developed for the assessment of existing culverts were increased 20% to account for future discharge projections (climate change), consistent with the NYSDOT Bridge Manual (2014);

• The minimum discharge to be conveyed by the structures was the 50-year recurrence interval event, consistent with recommendations in the NYSDOT Bridge Manual (2014);

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• Proposed culvert widths were a minimum of 1.25 times the bankfull width of the upstream channel per the New York State Department of Environmental Conservation (DEC) Stream Crossings: Guidelines and Best Management Practices manual. The bankfull widths of the upstream channel were determined from field survey data provided by the North Atlantic Aquatic Connectivity Collaborative (NAACC);

• Unless it was necessary to do so to convey the 50-year recurrence interval event, the existing grade of the road was assumed to remain constant; where it was necessary to raise the road profile, the combined improvements were configured not to increase upstream flood depths;

• Given the low depths of fill above the existing culverts, all proposed stream crossings were assumed to be three-sided precast concrete boxes with natural bottoms;

• The Manning’s n selected for the proposed crossings was selected for the channel substrate materials and thus ignores the lower roughness of the concrete walls and top; and,

• The opening height of the proposed culverts were assumed to be equal to that of the existing culvert. However, for cost estimating, the height of the structure was increased from the clear opening to account for DEC requirements to embed the structure beneath the streambed 20%.

Preliminary culvert dimensions for each crossing are summarized in Table 4. In general, expanding the width of the culvert to span the recommend 1.25 times the bankfull width was sufficient to convey at least the 2 percent ACE discharge (50-year recurrence interval) at all crossings except County Road 3 and the 1 percent ACE discharge (100-year recurrence interval) at most crossings. Due to the low depth of cover above the County Road 3 crossing, a 1-foot increase in the road profile of County Road 3 is recommended to convey the 2 percent ACE discharge without overtopping County Road 3. Table 4 also provides the Engineer’s Opinion of Probable Construction Cost for the proposed replacement culverts. These estimates were developed based on limited quantify takeoffs and recent unit price bid data contained in the NYSDOT Estimator worksheet. Uncertainty ranges corresponding to a Class V (planning-level) cost estimate as defined by AACEI were applied to the estimated cost to provide the anticipated range of cost for the proposed structures. Undersized Private Stream Crossings Rationale for Selection: In reviewing available data for development of this Plan, several private crossings were identified that cause an increase in upstream water surface elevations to varying degrees. Where such private crossings cause an increase in upstream water surface elevations that increase the flood risk to other residents, a corrective action may be warranted to reduce the flood risk to other residents. In addition to potentially increasing flood risk to upstream residents, undersized crossings may also restrict the migration of aquatic organisms and be more prone to clogging, failure, erosion, and closure due to overtopping.

Conceptual Mitigation: Public efforts to mitigate undersized private crossings should focus on education and outreach to owners of private crossings to communicate the economic (avoided flood damages) and environmental benefits of a right-sized stream crossing with the goal to convince private owners to self-fund improvements to their stream crossings. Further efforts to mitigate potentially undersized crossings should focus on those crossings that are downstream of structures that are not owned by the owner of the private crossing; such crossings may thus negatively impact other property owners if the crossing is undersized and increases upstream water surface elevations. Mitigation of such crossings may also demonstrate a public benefit that can qualify for public funding sources.

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Where there is an opportunity to mitigate potentially undersized crossings, Shumaker recommends these crossings be replaced with a larger structure that spans the channel and meets stream crossing guidelines established by DEC. These guidelines can be accessed at the link provided in the previous section which also provides additional information on the potential problems associated with undersized crossings.

Implementation Plan As the hazard ranking for each flood hazard summarized in Table 2 integrates the probability of occurrence, impact, spatial extent, warning time, and duration of the flood hazard, Shumaker recommends that the hazard ranking be used to prioritize flood mitigation actions. The prioritized list of flood mitigation actions discussed in the previous section is provided in Table 5.

Table 5: Prioritized List of Flood Mitigation Actions

Priority Mitigation Action Hazard Ranking

Comment

1 Implementation of an Emergency Notification System (anticipated to be via EverBridge®)

3.9

2 Replacement of Bostock Road crossing across Butternut Creek

2.7 Higher priority than CR 42 and CR 3 because of impact to Town police response

3 Replacement of County Road 42 crossing across Every Brook

2.6 Higher priority than CR 3 because of population disconnected from Town emergency responders

4 Mitigation of Repetitive Loss Properties Up to 2.1 Reduction of future flood damages and potential for loss of life or injury at known flood-prone properties

5

Replacement of County Road 3 crossing across Unnamed Stream and elevating approximately 850 feet of County Road 3 approximately one foot.

2.6 Lower priority than CR 42 across Every Brook because alternate routes available for emergency responders.

6 Replacement of County Road 42 crossing across Winchell Brook

2.6 Lower priority than CR 3 because sediment deposition at this site has been readily removed to reopen road.

7 Replacement of Red Maple Drive crossing across Butternut Creek

2.6

8 Replacement of undersized private stream crossings that increase flood risk to upstream structures

Up to 2.4

9 Replacement of High Point Mountain Road Crossings over Unnamed Brook

1.8 Recommended by FAC for prioritization

Funding Sources Project funding is a common challenge for implementation of public flood mitigation projects. As local, state, and Federal governments incur significant costs following natural disasters and would benefit from the reduction or elimination of future flood damage costs, several funding opportunities are available from these entities to decrease the financial burden of flood risk mitigation projects to communities or individual property owners. Given the numerous potential Federal, state, local, and private funding sources, the accompanying descriptions of their applicability, and the applicability of these funding sources to the Boiceville and West Shokan LFA, the list of potential funding sources has been provided separately as Appendix D.

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5.0 Additional Actions to Reduce Flood Hazards

Community Flood Hazard Mitigation Actions In addition to the recommended flood mitigation actions, Shumaker also considered input from the public, FAC, and Town Board, and its professional experience to recommend the following policies and minor actions that can be enacted by the Town on a shorter-time frame to reduce and prevent flood damage. These recommendations are summarized in Table 6 (on the following page).

Table 6: Community-Level Recommendations to Reduce Flood Risk

Community-Level Recommendations

1. Adopt a Riparian Setback Ordinance to conserve existing, and promote new, healthy riparian corridors of mature, woody vegetation. Stands of mature, woody vegetation along the streambanks will promote streambank stability, reduce streambank erosion, improve water quality, and improve the health of the riparian ecosystem. The Riparian Setback Ordinance may also function to manage development in unmapped flood-prone areas.

2. Maintain existing land uses that limit development in flood-prone areas. In particular, agricultural or undeveloped lands generally have lower flood risk than developed properties and can more easily co-exist with flooding while providing a community benefit. Therefore, continued conservation of open space and cultivation of productive agricultural fields is recommended.

3. Consider revising the local floodplain ordinance to extend the applicability of the ordinance to all flood-prone areas within Town, including those that are not currently mapped as Special Flood Hazard Areas by FEMA.

4. Increase community awareness that driving across flooded roads is dangerous and should be avoided. Prepare emergency personnel to close flood-prone roads, install flood warning signs along roadways subject to frequent flooding, and develop alternate routes for emergency responders.

5. Continue involvement in the Ulster County Multi-Jurisdictional Hazard Mitigation Plan; cross-identification of Town-wide Flood Hazard Mitigation Plan- or Boiceville and West Shokan LFA- recommended projects in the MJHMP could increase chances for project funding. In addition, look for opportunities to participate in disaster-resiliency programs at the local, county, state, or Federal level.

6. Support USGS efforts to maintain and operate stream gages on Esopus Creek, Bushkill, Little Beaver Kill, and other streams in the Town of Olive to provide improved information to estimate the magnitude of rare floods.

7. Increase understanding of flood hazards by reaching out to the local community. Educate real estate agents and potential buyers on the location of Special Flood Hazard Areas in relation to structures for sale.

8. Following floods, methodically collect, document and store information related to flood damage in the community. Note the date, duration, and cause of flooding (tropical storm, snow-on-rain, etc.), survey high water marks within the Town, document the days a business is closed or a resident displaced, and document public and private flood recovery costs to support future mitigation planning efforts.

9. To increase the Town's resiliency against flooding, adopt a local law or otherwise require that hydraulic designs (including both riverine, lacustrine, and stormwater drainage) of future projects are standardized, and include provisions that consider the effects of climate change. This requirement should also apply to privately-owned roads, stream crossings, and other development. Examples of such design guidelines and/or recommendations that increase peak discharges can be found in the NYSDOT Bridge Manual (2014) and DEC's Flood Risk Management Guidance (2019).

10. Flooding is a naturally-occurring hazard that is expected to continue, and likely worsen, in the future. Therefore, it is recommended that all development within flood-prone areas be designed assuming that flooding will occur. Specifically, resilient measures that support continued operation during, and quick recovery after, floods are recommended. Many of these recommendations are embodied in the Town’s floodplain development ordinance, but could also include such measures as on-site power generation, elevated driveways for emergency access during floods, and location of critical assets at higher elevations on a property.

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Community-Level Recommendations

11. Maintain and update the Town-wide Flood Hazard Mitigation Plan on a regular basis. Shumaker recommends updating the Plan on a time frame consistent with that of the Ulster County Multi-Jurisdictional Hazard Mitigation Plan – every five years.

Individual Flood Hazard Mitigation Actions In addition to the recommended Town-led flood mitigation actions, Shumaker also considered input from the public, FAC, and Town Board, and its professional experience to recommend the following policies and minor actions that can be enacted by the individual property owners to reduce and prevent flood damage. These recommendations are summarized in Table 7.

Table 7: Individual-Level Recommendations to Reduce Flood Risk

Property-Level Recommendations

1. Purchase flood insurance to insure your home, valuables, and family in event of future flood damage. In the event of flood damage, document the damage and retain all receipts. Work with the local emergency services coordinator to prepare and submit claims to FEMA.

2. Enroll in the New York Emergency Alerts System (https://alert.ny.gov/) and, when available, the Ulster County Emergency Notification System to receive important real-time information and announcements, including flood hazard and severe weather notifications, from the State and County.

3. Store personal valuables at higher locations in your home to reduce the potential that these valuables are damaged in the event of a flood.

4. Remove household chemicals, fertilizers, gasoline, and potential contaminants that you do not anticipate using and dispose of at an approved facility. For those items that you anticipate using, store at higher locations in your home to reduce the potential that these contaminants enter floodwaters during a flood event.

5. Store farm equipment, recreational vehicles, snowmobiles, and other motorized vehicles at high ground during periods of anticipated flood conditions to avoid damage to this equipment.

6. Plant appropriate, native plant species to establish healthy riparian corridors of mature, woody vegetation along streambanks to reduce the potential of future streambank erosion.

7. Relocate flood-prone utilities to higher locations in your structure.

8. Install sewer backflow valves on sewer/septic outfalls to prevent back-flooding of your home.

9. Anchor gas, oil, and fuel tanks to prevent their flotation during a flood event. Residents within the 500-year floodplain (Zone A, Zone AE, or stippled Zone X in the Flood Insurance Rate Maps) within the NYC West-of-Hudson watershed (the NYC West-of-Hudson watershed within the Town of Olive is identified in Figure 1) are eligible to apply for full funding of tank anchoring projects from the Catskill Watershed Corporation. A Tank Anchoring Program Application can be accessed at the following link:

http://cwconline.org/wp-content/uploads/2017/03/TankAnchoringApplication.pdf

10. Consider options to dry- or wet-floodproof your home. Section 5D and 5W of FEMA’s Engineering Principles and Practices for Retrofitting Flood-prone Residential Structures provides additional details on available flood-proofing options and performance criteria

https://alert.ny.gov/

http://cwconline.org/wp-content/uploads/2017/03/TankAnchoringApplication.pdf

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Community Rating System The Community Rating System (CRS) is a program developed by the Federal Emergency Management Agency (FEMA) that is voluntary to municipalities that participate in FEMA’s National Flood Insurance Program (NFIP). The intent of the CRS program is to reward participating communities who implement activities that exceed minimum NFIP requirements and work toward the three goals of the CRS:

1. Reduce and avoid flood damage to insurable property; 2. Strengthen and support the insurance aspects of the NFIP; and, 3. Foster comprehensive floodplain management.

Communities participating in the CRS are rewarded through reductions in flood insurance rate premiums that apply to all policies within the Town; i.e., individual residents of a community will receive a reduction in their flood insurance premiums as their community receives a better CRS classification. The flood insurance rate reductions are derived from a CRS Class rating system that is based on the amount of Credit Points obtained. Credits are assigned for 19 activities under four major categories as show in Table 8. Note in Table 8 that the average points earned are often much less than the maximum points available, demonstrating that receipt of these points are not a given. The various CRS classes, credit points required, and premium discounts are shown in Table 9.

Table 8: Credit Points Awarded for CRS Activities (reproduced from FEMA, 2017)

Activity Maximum Possible Points

Maximum Points Earned

Average Points Earned

Percentage of Communities

Credited

300 Public Information Activities

310 Elevation Certificates 116 116 38 96%

320 Map Information Service 90 90 73 85%

330 Outreach Projects 350 350 87 93%

340 Hazard Disclosure 80 62 14 84%

350 Flood Protection Information 125 125 38 87%

360 Flood Protection Assistance 110 100 55 41%

370 Flood Insurance Promotion 110 110 39 4%

400 Mapping and Regulations

410 Flood Hazard Mapping 802 576 60 55%

420 Open Space Preservation 2,020 1,603 509 89%

430 Higher Regulatory Standards 2,042 1,335 270 100%

440 Flood Data Maintenance 222 249 115 95%

450 Stormwater Management 755 605 132 87%

500 Flood Damage Reduction Activities

510 Floodplain Management Planning 622 514 175 64%

520 Acquisition and Relocation 2,250 1,999 195 28%

530 Flood Protection 1,600 541 73 13%

540 Drainage System Maintenance 570 454 218 43%

600 Warning and Response

610 Flood Warning and Response 395 365 254 20%

620 Levees 235 207 157 0.5%

630 Dams 160 99 35 35%

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Table 9: CRS Classes, Credit Points, and Premium Discounts (reproduced from FEMA, 2017)

CRS Class Credit Points Premium Reduction

In Special Flood Hazard Area* Outside Special Flood Hazard Area*

1 4,500 + 45% 10%

2 4,000 to 4,499 40% 10%

3 3,500 to 3,999 35% 10%

4 3,000 to 3,499 30% 10%

5 2,500 to 2,999 25% 10%

6 2,000 to 2,499 20% 10%

7 1,500 to 1,999 15% 5%

8 1,000 to 1,499 10% 5%

9 500 to 999 5% 5%

10 0 to 499 0 0%

* Special Flood Hazard Areas include Zones A, Zone AE, Zone AH, and Zone AO in the Town of Olive

As shown in Table 9, a minimum of 500 credits are required to become a Class 9 community and receive an associated 5% reduction in flood insurance premiums. It is important to note that the flood insurance premium reductions vary depending if the insured properties are located within or outside the Special Flood Hazard Area (SFHA). Regarding the anticipated reductions in flood insurance premiums if the Town were to enroll in the CRS, there are 36 NFIP policies in force that insure a total of $10,952,700 of property within the Town (DEC, 2018). Of these 36 policies, 10 properties (residential) are located within the SFHA. The average flood insurance policy in the Town as of 2018 is approximately $1,674/year; for those 10 homes in the SFHA, the average is $5,152/year. With 36 policies in force, the flood insurance premium savings per year, if the Town were to become a Class 9 community, would be approximately 36 x $1,674 x 5% reduction = $3,013/year. As shown in Table 9, additional reductions in flood insurance premiums can be realized as the CRS Class decreases, however each CRS class reduction requires additional Credit Points and associated effort to obtain and maintain. Prerequisites to becoming a Class 9 community are identified in Section 211.a of the CRS Coordinators Manual (FEMA, 2017) and include, but are not limited to: being in the NFIP for a minimum of one year, being in full compliance with the minimum standards of the NFIP, maintaining FEMA elevation certificates for all new buildings and substantial improvements within the SFHA, and taking certain actions regarding repetitive loss properties within the community. Many of these prerequisite actions are already undertaken by the Town. However, there is effort and cost associated with obtaining and maintaining the credit points necessary to achieve a Class 9 designation that should be compared to potential flood insurance premium costs savings. Shumaker recommends that the Town regularly review the program prerequisites, level of effort, and cost for obtaining a Class 9 CRS designation. At a minimum, the decision to participate in the CRS should be re-visited every time new Flood Insurance Rate Maps are adopted by the Town. While the minor reductions in flood insurance did not justify the resources necessary for the Town to enroll in the CRS and become a Class 9 community during development of the Boiceville and West Shokan LFA, if conditions change and the Town does decides to enroll in the CRS in the future, they can leverage existing measures already in place to acquire credit points to enter a Class 9 or higher CRS level. Referring to Table 8, credit points that may be readily available to the Town include Activities 430 Higher

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Regulatory Standards, 440 Flood Data Maintenance, 450 Stormwater Management, and 510 Floodplain Management. For activity 440, the effective date for the Flood Insurance Study and associated DFIRM panels are recent (November, 2016) and can be easily be maintained and distributed. Finally, the completion of mitigation actions and recommendations within this Town-wide Flood Hazard Mitigation Plan and the Boiceville and West Shokan LFA (including production of these plans themselves) provides multiple opportunities for acquiring credit points under activity 510 Floodplain Management Planning, activity 520 Acquisition and Relocation, activity 530 Flood Protection, and activity 610 Flood Warning and Response. For example, implementation and participation in the County’s emergency notification system should qualify for Activity 610 Flood Warning and Response which carries a maximum credit of 395 credit points (average points earned = 254).

6.0 Summary With funding from the Cornell Cooperative Extension of Ulster County and a grant from the Hudson River Valley Greenway, Shumaker coordinated with the Town, the AWSMP, and the Town of Olive Flood Advisory Committee to prepare this Town-wide Flood Hazard Mitigation Plan. As part of this plan, Shumaker consolidated flood hazards identified in previous studies, supplemented this list with additional hazards identified by the FAC, and ranked the hazards in a manner consistent with the Ulster County Multi-Jurisdictional Hazard Mitigation Plan to identify and rank a total of 38 flood hazards within the Town of Olive. As this Town-wide Flood Hazard Mitigation Plan was developed to extend the Boiceville and West Shokan LFA, these 38 flood hazards are in addition to those hazards identified in the Boiceville and West Shokan LFA.

Based on discussion with the FAC and review of the hazard ranking, a total of eight priority actions were identified to mitigate flood risk within the Town. The majority of the identified priority actions were the replacement of undersized road crossings of streams that frequently overtop and have a high potential to restrict access for emergency responders during future floods. Mitigation of Repetitive Loss Properties was also identified to avoid future damages and reduce risks of loss of life or injury at these flood-prone properties. An emergency notification system was also identified as a top priority for the Town to provide residents an opportunity to protect flood-prone property and/or evacuate from flood-prone areas; the benefits of this action can be realized immediately upon its implementation. Finally, in addition to infrastructure projects and programmatic actions to mitigate the long-term flood risk in the Town, Shumaker also recommended a series of actions that can be undertaken in the short-term by the Town or local residents to immediately reduce flood risk throughout the Town.

Plan Acceptance This Town-wide Flood Hazard Mitigation Plan was presented by Shumaker to the Town Board of the Town of Olive on January 8, 2019. No comments were received from the public, the Town Board, or the Town during the open comment period following this presentation. On February 12, 2019, this Town-wide Flood Hazard Mitigation Plan was finalized and accepted by the Town Board of the Town of Olive.

7.0 References Ashokan Watershed Stream Management Program (2018). Maltby Hollow Brook Stream Feature Inventory and Management Recommendations. Prepared by Barton & Loguidice, DPC. September.

Cornell Cooperative Extension of Ulster County (2017). Local Flood Analysis for the Hamlets of Boiceville and West Shokan. Prepared by Woidt Engineering and Consulting, PC. November.

Federal Emergency Management Agency (FEMA; 2013). Local Mitigation Planning Handbook. March.

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Federal Emergency Management Agency (FEMA; 2016). Flood Insurance Study Number 36111CV001B. Ulster County, NY (All Jurisdictions).

Federal Emergency Management Agency (FEMA; 2017). National Flood Insurance Program Community Rating System Coordinator’s Manual, FIA-15/2017.

New York State Department of Environmental Conservation (DEC; 2018). Federal Emergency Management Agency (FEMA) National Flood Insurance Policy (NFIP) Dataset. March 31.

New York State Department of Transportation (NYSDOT; 2014). Bridge Manual (US Customary Edition), Addendum #3 to 4th Edition.

Ulster County Department of Emergency Communications/Emergency Management (2017). Multi-Jurisdictional Hazard Mitigation Plan for Ulster County, NY. Prepared by URS Group, Inc. September.

Ulster County New York Rising Community Reconstruction Planning Committee (Ulster NYRCRP Committee; 2014). New York Rising Community Reconstruction Plan for Ulster Communities. Prepared by AKRF, Inc., CDM Smith, Inc., Arch Street Communications, Inc., and Elan3 Consulting.

Ulster County Soil and Water Conservation District. (2015). Bush Kill Stream Management Plan. Prepared in cooperation with the New York City Department of Environmental Protection.

TOWN OF OLIVE LOCAL FLOOD ANALYSIS

APPENDIX D: FLOOD MITIGATION FUNDING OPPORTUNITIES

TOWN OF OLIVE ULSTER COUNTY, NEW YORK

Prepared for:

Town of Olive

45 Watson Hollow Road West Shokan, NY 12494

In partnership with:

Cornell Cooperative Extension of Ulster County 3130 Route 28 Shokan, NY 12481

Prepared by:

Shumaker Consulting Engineering and Land Surveying, DPC 143 Court Street Binghamton, New York 13901

February 13, 2019

1

Appendix D: Flood Mitigation Funding Opportunities

Funding Source Purpose Cost Share Eligibility

Federal Funding Sources

Federal Emergency Management Agency (FEMA) Hazard Mitigation Grant Program (HMGP)*

Implementation of cost-effective hazard mitigation measures to reduce the risk of loss of life and property. Measures include structure acquisitions, structure elevations, structure relocation and/or reconstruction, hazard mitigation planning, floodproofing of historic properties, green infrastructure, and structural retrofits.

Up to 75% funding of project costs

State, local, and tribal governments and private non-profits, only after declaration of a Presidentially-declared Major Disaster

Federal Emergency Management Agency (FEMA) Flood Mitigation Assistance (FMA)**

Reduce or eliminate the risk of repetitive flood damage to structures insurable under the National Flood Insurance Program through advance planning, community-flood mitigation planning and projects, technical assistance, flood mitigation planning, and individual property mitigation projects.

Up to 75% funding of project costs, limited to $100,000 for community flood mitigation advance assistance, $10,000,000 for community flood mitigation projects, and $25,000 for local mitigation planning. Up to 90% and 100% for Repetitive Loss and Severe Repetitive Loss properties, respectively.

State, local, and tribal governments having a Hazard Mitigation Plan

Federal Emergency Management Agency (FEMA) Pre-Disaster Mitigation (PDM)*

Planning and projects to reduce natural hazard risk to populations and structures and avoid use of future Federal funding following disasters.

Up to 75% funding of project costs; up to 90% for impoverished communities with population of less than 3,000.

State, local, and tribal governments having a Hazard Mitigation Plan

Federal Emergency Management Agency (FEMA) Repetitive Flood Claims Grant**

Reduction or elimination of long-term flood risk to structures insured under the National Flood Insurance Program that have had one or more claim payments for flood damages.


State, local, and tribal governments unable to provide the local cost share for FEMA’s Flood Mitigation Assistance program.

Federal Emergency Management Agency (FEMA) Risk Mapping, Assessment, and Planning Program (Risk MAP)

Identification of flood risk and promoting planning and development practices to reduce future flood risk.


Municipalities administering the minimum requirements of the National Flood Insurance Program.

2


Federal Emergency Management Agency (FEMA) Public Assistance Program

Assistance for debris removal, life-saving emergency protective measures, and the repair, replacement, or restoration of disaster-damaged publicly-owned facilities, and the facilities of certain private non-profits.

Not less than 75% funding of project costs

State, local, and tribal governments and private non-profits, only after declaration of a Presidentially-declared Major Disaster

Natural Resources Conservation Service (NRCS) Emergency Watershed Protection – Recovery*

Construction of economically-, environmentally-, and socially-sound flood recovery measures to safeguard lives and property as the result of a natural disaster. Debris removal, streambank repair, and erosion control are eligible provided the problems did not exist prior to the natural disaster.

Up to 75% funding of construction costs

Conservation Districts and Federal, state, local, and tribal governments

Natural Resources Conservation Service (NRCS) Emergency Watershed Protection – Floodplain Easement

Removal and relocation of structures and subsequent restoration of lands that have been 1) damaged by floods in the previous year, 2) damaged by floods twice within the previous 10 years, or 3) would contribute to the restoration of flood storage and flow or control erosion.

Up to 100% funding Private, local, or state property owners

Natural Resources Conservation Service (NRCS) Watershed Protection and Flood Prevention*

Design and construction of cost-effective projects to prevent erosion, flood damage, and sedimentation in watersheds up to 250,000 acres in which at least 20 percent of the project’s benefits accrue to agriculture

Up to 100% up to a maximum of $5,000,000 without Congressional approval

Public agencies or non-profit organizations

US Army Corps of Engineers (USACE) Section 14 Emergency Streambank and Shoreline Protection*

Study, design, and construction of economically-justified and environmentally-sound streambank protection works to protect public facilities (roads, bridges, water supply, wastewater treatment, etc.) and non-profit public facilities (churches, hospitals, etc.)

Up to 100% funding of feasibility studies up to $100,000; 50% thereafter. Up to 65% of design and construction costs. Total feasibility, design, and construction Federal cost share not to exceed $5,000,000 for any single project.


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US Army Corps of Engineers (USACE) Section 205 Flood Damage Reduction Projects*

Study, design, and construction of economically-justified, environmentally-sound, and technically-feasible small flood damage reduction projects including, but not limited to, channel improvements, floodplain modifications, and levees.

100% funding of feasibility studies up to $100,000; 50% thereafter. Up to 65% of design and construction costs. Total feasibility, design, and construction Federal cost share not to exceed $10,000,000 for any single project.


US Army Corps of Engineers (USACE) Section 206 Aquatic Ecosystem Restoration Projects*

Study, design, and construction of cost-effective projects in the public interest which restore aquatic ecosystems for fish and wildlife including, but not limited to, wetland restoration, river restoration, and dam removal.

100% funding of feasibility studies up to $100,000; 50% thereafter. Up to 65% of design and construction costs. Total feasibility, design, and construction Federal cost share not to exceed $500,000 for any single project.


US Army Corps of Engineers (USACE) Section 208 Clearing and Snagging Projects*

Study, design, and construction of channel clearing and excavation projects to reduce nuisance flooding caused by debris and minor shoaling of rivers that are economically-justified, environmentally-sound, and feasible.

100% funding of feasibility studies up to $100,000; 50% thereafter. Up to 65% of design and construction costs. Total feasibility, design, and construction Federal cost share not to exceed $10,000,000 for any single project.


US Department of Housing and Urban Development (HUD) Community Development Block Grant

Ensure decent, affordable housing for low- and moderate-income persons, prevent or eliminate slums or blight, and/or address community development needs that pose a serious and immediate threat to the health or welfare of the community (such as flooding).

Up to 100% of project costs Local or state governments

Federal Highway Administration Emergency Relief Program

Funds for the repair or re-construction of highways that have suffered serious damage as the result of a natural disaster or catastrophic events from an external cause.

Up to 80% of project costs, with several exceptions that allow up to 100% of project costs.

States may apply for funding for Federal-aid highways only

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State Funding Sources

Department of Environmental Conservation (DEC) Flood Mitigation Grant

Flood debris removal and streambank stabilization and restoration

Up to 100% of project funding up to a maximum of $500,000

Municipalities

Department of Environmental Conservation (DEC) Trees for Tribs Program

Planting of trees along stream corridors to prevent erosion, increase flood storage, improve water quality, and improve aquatic and riparian habitat.

Up to 100% funding for plant materials and technical assistance

Property owners, municipalities, and conversation organizations outside of NYC Watershed area.

Department of Environmental Conservation (DEC) Hudson River Estuary Grants Program (HREP)

To implement priorities outlined in the Hudson River Estuary Action Agenda aimed at conserving or improving clean water; fish, wildlife and their habitats; waterway access; the resiliency of communities; and river scenery.

Up to 85% of project funding

Not-For-Profit, governmental or quasi-governmental entity, tribal organization

Department of Environmental Conservation (DEC) Water Quality Improvement Project Grant

Projects to reduce non-point source water pollution (e.g., excessive streambank erosion), restore aquatic habitat, or acquire lands for source water protection.

Up to 75% of project funding

Municipalities, municipal corporations, conservation districts, not-for-profit corporations, and regulated municipal separate storm sewer systems.

Department of Labor Neighborhood Rebuilding Corps

Provision of labor to assist in flood recovery efforts Up to $12,000 per temporary employee Municipalities

Department of Homeland Security and Emergency Services (DHSES) Emergency Management Performance Grants**

State-administered Federal grants from FEMA to assist local governments in providing a system of emergency preparedness for the protection of life and property.

Up to 50% of project funding Municipalities

New York State Consolidated Funding Application

Consolidated application for multiple state-administered economic development funding sources; NY State will identify applicable sources.

Varies by funding source Varies by funding source

https://www.dec.ny.gov/lands/5104.html

https://www.dec.ny.gov/lands/5104.html

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Local Funding Sources

Ashokan Watershed Stream Management Program Stream Management Implementation Program (SMIP)

Funding program for LFA communities to implement LFA recommendations that have off-site flood reduction benefits. Eligible projects include floodplain restoration and reconnection, stream restoration, infrastructure to reduce in-stream depth and/or velocity, and/or removal of hydraulic constrictions. Ineligible projects include flood walls, berms, or levees, dredging, routine annual maintenance, or replacement of privately-owned bridges, culverts, or roads.

Up to 100%

Municipalities with approved Local Flood Hazard Mitigation Plans (LFHMP)

Ashokan Watershed Stream Management Program Catskill Streams Buffer Initiative (CSBI)

To inform and assist landowners in improved stewardship of riparian areas through protection, enhancement, management or restoration of streamside vegetation and riparian areas. The CSBI program provides a list of recommended actions of which can be funded and installed on individual properties to promote positive riparian stewardship, such as tree and shrub plantings, debris management, invasive species management, and bioengineered streambanks are some examples

Up to 100%

Streamside landowners, municipalities within the Ashokan Reservoir Watershed

Catskill Watershed Corporation Flood Hazard Mitigation Implementation Program

Funding of projects to decrease flood risk to residences, businesses, and/or communities and elimination of potential water quality hazards. Eligible projects include relocation assistance, alteration of public infrastructure, property protection measures, elimination of potential pollution sources, stream-related construction work, stream debris removal, and oil and propane tank anchoring.

Structural flood control projects (levees, berms, floodwalls), stream dredging or channelization, and maintenance activities are ineligible.

Varies; generally 100%, but limited to 75% for property protection measures, community-wide pollution source elimination, and wastewater.

Municipalities; also property owners for property protection measures. Except for tank anchoring, stream debris removal, and relocation assistance for properties participating in the NYCFFBO, other projects need to be recommended in the community’s Local Flood Hazard Mitigation Plans (LFHMP)

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Catskill Watershed Corporation Sustainable Community Planning Program

Funding of revisions to local zoning codes or zoning maps or to upgrade comprehensive plans to identify areas that can serve as new locations for residences and/or businesses after purchase under the NYCFFBO.

100%, up to $20,000

Municipalities with approved Local Flood Hazard Mitigation Plans (LFHMP)

Flood Control and/or Drainage District

Creation of a Flood Control and/or Drainage District to fund the planning, implementation, and maintenance of projects to reduce flood risk and administer a public program to reduce flood risk damages. Formation of a Town Special District would be required to levy user fees and/or taxes to fund the costs of the District. In other parts of the country, Flood Control Districts have been used to fund enrollment in FEMA’s Community Rating System that upon achievement of certain public information and floodplain management activities, can reduce flood insurance rates for local ratepayers and generate a net savings to individual property owners.

Not applicable Not applicable

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New York City-Funded Flood Buyout Program (NYCFFBO)

Acquisition of properties that are:

o Supported by the local community and are: ▪ Recommended by a hydraulic study

(including a LFHMP); ▪ Qualify for relocation assistance from

the Catskill Watershed Corporation; or, ▪ Recommended for implementation of

the preferred alternative for a stream restoration project;

o At risk of damage or destruction from erosion hazards;

o Located within a Special Flood Hazard Area and at least has been previously flooded and experienced significant damage, but not necessarily Substantial Damage as defined by FEMA; or,

o Have been previously flooded and can be relocated on the existing parcel outside of the 100-year and 500-year floodplain.

Up to 100%

Properties with willing property owners and, as noted above, supported by local communities.

Private Funding Sources

Individual Property Owners

While several funding sources are available to decrease financial burdens to individual property owners, individual property owners are able to self-finance any or all of the recommendations in this LFHMP.

Not applicable No restrictions

Not-for-Profit Corporations or Private Foundations

Where project benefits align with the goals of Not-for-Profit Corporations or private foundations, private funding could be used to fund portions of the project. Projects most likely to align with such organizations are those that have stated organizational goals to improve the environment.

Not applicable Not applicable

* Benefit-cost analysis required demonstrating benefits in excess of costs (i.e., Benefit-Cost Ratio in excess of 1.0)

** Benefit-cost analysis required demonstrating benefits in excess of costs (i.e., Benefit-Cost Ratio in excess of 1.0) not required, but used to prioritize funding allocation

TOWN OF OLIVE LOCAL FLOOD ANALYSIS APPENDIX C:...

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