Kinney Run and Tributary No. 10 Stormwater Analysis Abstract Kinney Run, an 8.288 square kilometer (3.20 square mile) watershed, and an Unnamed Tributary No. 10 Scott Township, a 5.698 square kilometer (2.20 square mile) watershed, are tributaries to the Susquehanna River within the Act 167 Study for Susquehanna River Tributaries, Columbia County, Pennsylvania. Originating in Scott Township, their headwaters are in moderate to steeply sloping uplands and then follow their paths through a joint flood plain to their outlets at the Susquehanna River. The analysis of the stormwater problems for these watersheds presented unique problems for modeling purposes. Natural and manmade conditions within the watershed have created impacts on downstream peak discharges. Analysis of the stormwater problems was performed using a combination of the NRCS TR-20 watershed model and the Army Corp HEC-RAS Hydraulic model. Trial and error was required to determine the discharge at several points within each watershed. This required first using TR-20 and its divert and reservoir storage routines to determine peak flows at various locations. These values were then used to perform HEC-RAS analysis. The discharge quantity and the elevations were compared at critical points in the two models. Adjustments were then made in each model until the peak discharges and discharge elevations in both models coincided. Once the existing condition models were calibrated in this manner, additional conditions evaluations were performed to determine their effects on downstream peak discharge. They include: (1) effects of future development within the watershed with no stormwater controls, (2) reduction in flood plain storage by filling the areas within the limits permitted by flood plain regulation; and (3) a combination of flood plain fill and future development without stormwater controls. Watershed analysis has identified a number of areas where stormwater is presently stored and results in reduction of downstream peak discharges. Many of these areas are in areas subject to intensive pressure for development. The analyses have also resulted in considerable discussion as to the types of stormwater Best Management Practices (BMPs) that may be needed to control impacts of future development on downstream stormwater discharges. In addition to the standard infiltration and detention or retention Best Management Practices, a need to preserve the natural and unintentionally man-made storage areas at their present capacity exists. Preservation of these stormwater storage areas will affect the value of these areas for their owners and depending upon the method used could be considered a taking of landowners’ rights. Introduction Kinney Run and Tributary No. 10 to the Susquehanna River in Scott Township are only two of forty-one watersheds being studied as part of an Act 167 Watershed Phase II Plan preparation for the Susquehanna River Tributaries, Columbia County, Pennsylvania. Kinney Run flows to its outlet at Bloomsburg through a very flat gradient (0.002 m/m) stream channel in the Susquehanna River flood plain. The stream channel flows parallel to the river through the common flood plain for 3230 meters (10,600 feet) and has tributary areas within the flood plain as well as additional upland areas. During major flood events, Kinney Run usually experiences flooding in its flood plain due to stormwater runoff from its drainage area. Kinney Run then returns its stormwater discharge to within channel area, before the river floods into it again.

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Tributary No. 10 also flows to its outlet with the river in Scott Township through the joint Susquehanna River flood plain for a distance of 1931-meters (6336 feet). During major flood events Tributary No. 10 follows the same flooding pattern as Kinney Run. The problem of managing stormwater for both streams has been recognized for a number of years. Several proposals have been developed to divert them directly to the river at different locations. The description of the problems and the unique challenges for analyzing their peak discharges are as follow: Eroded soil from upland areas has silted in some of the stream channels at the upland- flood plain interface. In some cases the channels are non-existent. There are a number of stormwater detention areas within the flow paths of Kinney Run and Tributary No. 10. These areas consist of both natural wetlands and stormwater storage areas created by railroad and highway fills within the watersheds. Many of these stormwater storage areas are not recognized as such and are located in areas under extensive pressure for development. Some of the areas along U.S. Route 11 are considered so valuable for commercial development that developers are looking for wetland mitigation sites in order to develop them. Many of the stormwater detention areas are within the designated FEMA Flood Insurance Plans. Several large ones that were created by roadways have not been identified in the FEMA Flood Insurance Plans as being located within the 100-year flood plain. In the watershed there are two locations where stormwater flow is diverted from the Kinney Run channel to either Tributary No. 10 or the Susquehanna River. Major differences in the 100-year frequency peak discharges were noted between the Town of Bloomsburg and the Scott Township FEMA studies for Kinney Run. The Town of Bloomsburg study indicates a 100-year discharge of 8.41 cubic meters/second (297 cfs) at the mouth, while the Scott Township study indicates a 100-year discharge of 38.51 cubic meters/second (1360 cfs) upstream from the mouth at the Scott Township boundary with Bloomsburg. Kinney Run Watershed and Problem Description The Kinney Run watershed with 8.299 square kilometer (3.20 square mile) drainage area is presented as Figure 1. The Kinney Run watershed originates in rolling upland topography with numerous small steep gradient tributaries (grades range from 0.02 to 0.08 meters/meter) that intersect the main flat gradient channel (0.002 meters/meter) throughout its length. The main channel transverses 1931-meters (6336 feet) in the joint floodplain with the river. During the last thirty-five years, there has been extensive residential and commercial development within the watershed. The upland land use has shifted from agricultural production having extensive land conservation treatment to residential developments and a few commercial enterprises, many of which have no stormwater detention and/or retention systems. The flatter sloped land areas of the watershed have also experienced extensive growth, with a high percentage of that development being commercial enterprises. Since the portion of the watershed within the Town of Bloomsburg was extensively developed, most of the new growth is occurring in Scott Township. Kinney Run stormwater problems have created considerable controversy between Bloomsburg and Scott Township. Both municipalities have independently addressed stormwater concerns by developing and implementing their own municipal stormwater ordinance within the last 10-years. Until the Act 167 study, Kinney Run was not looked upon as a complete watershed in order to determine the effects of the stormwater ordinances.

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Development with the increase in impervious areas and installation of the stormwater drainage pipes and channel systems has not only increased the discharges from subwatershed areas, but has accelerated the movement of stormwater downstream. Due to these changes in discharge, many of the upslope channels are eroding at an accelerated rate. The sediment is carried downstream to the valley interface where it is deposited as the channel grade flattens out. The sediment deposition results in reduced channel conveyance capacity and in some cases, the sediment has completely filled the channels. A portion of Kinney Run, east of Central Road, is one of the areas where the channel has been silted in. Not only has this occurred but also the formerly farmed area has reverted to a wetland. At this location, (Diversion-1 on Figure 1), some of Kinney Run’s stormwater flow diverts to Tributary No. 10 through the wetland area. After the June 1972 Agnes Flood, in order to relieve flooding problems in Bloomsburg along Kinney Run, a structure, (Diversion-2 on Figure 1) was constructed to divert a portion of the flood flows directly to the Susquehanna River via a channel and large diameter pipe (2100 millimeter) under the airport runway. Several past studies have recommended other diversions of Kinney Run to the Susquehanna at several locations within Scott Township and just east of Catherine Street in Bloomsburg. These diversions were recommended to relieve flooding of potentially developable land in Scott Township and to reduce flooding from Kinney Run in Bloomsburg. Within Kinney Run’s joint flood plain with the river there are a number of obstructions and natural wetlands that detain stormwater runoff and reduce peak discharges. The North Shore railroad bed and U.S. Route 11 were constructed parallel to the river, and in many places, through areas of wetlands or hydric soils. The wetlands and obstructions that affect the stormwater peak discharge locations are noted on Figure 1 and a description is included in Table 1. Beavers create additional stormwater level problems, as they build dams and block culverts. The result of the beavers’ labor raises stormwater levels and increases the area inundated. It also reduces the available stormwater detention volume within those areas. The area identified as Stormwater Storage #2 on Figure 1 has been zoned as Flood Overlay District by Scott Township. However, other than not developing within the actual floodway, the major requirement of the zoning regulations is that the first floor of any building within this area must be constructed 0.4572 meters (1.5 feet) above the designated 100-year flood level in the FEMA Flood Insurance Plan. Historically, serious floods along Kinney Run have been accompanied by major flooding on the Susquehanna River. During the Agnes and January 1996 floods, Kinney Run first experienced flood plain flooding from stormwater discharges from within its watershed. Stormwater runoff returned to within stream banks and then, approximately 24 hours later again flooded due to backwater from the River. Other flood events have occurred from thunderstorms and that flooding was strictly from stormwater from within the Kinney Run drainage area. Most of the thunderstorm events have been of short duration and the flooding problems occurred in the steeper portions of the watershed or at the flood plain interface. Within the Bloomsburg town limits there have been problems where the absence of pipe drains or inadequate capacity of existing drains has resulted in street and basement flooding. Kinney Run Analysis Procedure The joint headwaters area for Kinney Run and Tributary # 10 was modeled using the divert routine within TR-20. The overtopping elevation of Central Road and a private road to the

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east of Central road are identical and act as dams to create a large ponding area between them. These roadways were used to calibrate stormwater diversion cross-sections. They were then used to determine the amount of watershed discharge contributing to either Kinney Run or Tributary # 10 during various storm events. Due to the flat channel gradient (0.002 meters per meter) of a large portion of the Kinney Run channel, the number of obstructions and the presence of large and numerous wetlands within the watershed, it was necessary to survey numerous valley cross-sections in order to analyze the watershed. The valley cross-sections were used in the US Department of Agriculture, Natural Resource Conservation Service (formerly the Soil Conservation Service) TR-20 Project Formulation Model. This model was selected because of its versatility in analyzing multiple structures within a watershed created by obstructions, its ability to analyze diverted flow and its ability to utilize a valley routing routine where stormwater storage occurs without a downstream obstruction. In addition, the HEC-RAS model was used to help calibrate the TR-20 model discharges from its outlet to the river to upstream of the diversion structure. The existing conditions TR-20 model was run and calibrated by use of the HEC-RAS model and FEMA reports. The calibrated model was then run for future development conditions. Due to the pressure to fill and develop many stormwater detention areas within the watershed, the model was run with fill placed in some of the flood plain and wetland areas. In no case was fill placed within the designated floodway or within 15.24 meters (50 feet) of the top of a stream bank where there was not a designated floodway. Kinney Run Analysis Results The peak discharges for various locations and conditions were analyzed. The conditions analyzed were: (1) Existing Conditions (2) Future Build-out Condition with no Flood Plain Fill (3) Existing Conditions with Detention Area Fill and (4) Future Build-out with Detention Area Filling. Table 2 provides the results of the four conditions evaluated at critical locations within the watershed. The analysis locations are identified on Figure 1. Although development within the watershed increased the downstream peak discharge for every storm, flood plain fills had a greater impact at the lower end of the watershed than development alone. This was due to the location of the flood plain fill areas and the cumulative effect of reduced storage capacity. At the Bloomsburg/Scott Township boundary line, the increased discharge due to development within the watershed ranged from 8.7% to 12.4% percent for the 2 through 100-year storms, while the combination of development with flood plain fills resulted in increased discharges ranging from 35.2% to 44.5%. The analysis for the diversion system near the airport provided a challenge. The diversion system was designed to allow baseflow and a portion of the stormwater discharge to flow through the Kinney Run channel to the river at the Bloomsburg Town Park. However, the Catherine Street and Recycling Center access road 1500-millimeter (60-inch) diameter culverts along with their road-fills, acted as dams. Stormwater runoff from within Bloomsburg was impounded by Catherine Street, so that it along with the 1500-millimeter (60-inch) diameter culvert under the road to the recycling center, adversely affected the discharge at the diversion system. The portion of the upstream flow reaching the diversion structure that actually flowed to the river through Kinney Run ranges from 33% for the 2-year storm to 15% for the 100-year storm. The remainder of the discharge flows to the river either through the 2100 millimeter (84- inch) diameter conduit under the airport runway or overland around the eastern end of the runway.

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Plans to increase the length of the runway and to raise its level are being developed. If this happens without evaluating the impact these changes would have on the existing stormwater discharge patterns, the result could be significant increase in stormwater discharge quantities and flood levels along Kinney Run both upstream and downstream from the diversion structure. Tributary No. 10 Watershed and Problem Description Tributary No. 10, a 5.698 square kilometer (2.20 square mile) watershed (Figure 2), like Kinney Run, originates in rolling upland areas with two primary tributaries that intersect the main flat gradient channel in the joint flood plain with the Susquehanna River. It has experienced considerable development in these joint flood plain areas, but still has a number of stormwater storage areas within them that are not yet developed. Within Scott Township, most areas have an overlying zoning as Floodway District. However, other than not developing within the actual floodway, the major zoning requirement is that the first floor of any building within this area be constructed 0.4572 meters (1.5 feet) above the designated 100-year flood level in the FEMA Flood Insurance Plan. Most of the FEMA designated flood plain is based upon elevations representing backwater from the Susquehanna River. Only a small portion of the designated flood plain north of U.S. Route 11 is based upon upland discharges controlling the 100-year flood level. An area zoned for commercial development on the western side of Shaffer Hollow Road is lower in elevation than the designated flood plain on the eastern side of the roadway. This area has not been identified as being within the 100-year flood plain although it has a history of flooding. The only outlet for stormwater accumulating in this area is through a 366-meter (1200 feet) long 380- millimeter (15-inch) diameter terra-cotta pipe installed in the 1930’s as farm drainage. This drainpipe (Figure 3) is the responsibility of the property owner whose lands it crosses and is failing in a number of places. During winter and spring seasons, the homeowners adjacent to this drainpipe complain that it causes wet basements and that their sump pumps run constantly. Some of the back yards of the homes along the east side of Shaffer Hollow Road are designated as not only flood plain, but also floodway on the FEMA FIP map. Since the FEMA map was prepared, the stream channel has been relocated from its original position in the valley bottom to a side hill location. On the lower side of the relocated channel is a dike that is regularly overtopped by stormwater. After every large stormwater runoff event, where the dike overtops, landowners complain to the Scott Township Supervisors and request that the channel and dike be improved to prevent this overtopping. The two major tributaries are conveyed by culverts and/or bridges under U.S. Route 11 and the North Shore Railroad to the main channel of Tributary No. 10 in the joint flood plain with the river. Due to the reduction in channel grade at these locations, there have been considerable problems with sediment deposition and the resulting need to remove it from the channels to maintain channel hydraulic capacity. The channel transverses 1931-meters (6336 feet) in the joint flood plain with the river. Stormwater peak discharges in this channel section are reduced by detention in the numerous ponds, wetlands and obstructions along its entire length. Beavers create additional stormwater level problems, as they build dams and block culverts. The result of the beavers’ labor raises stormwater levels and increases the area inundated. The wetlands and obstructions that affect the stormwater peak discharge locations are noted on Figure 2 and a description is included in Table 3.

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Tributary # 10 Analysis Procedure Valley cross-sections were surveyed so that more accurate modeling of the effect of flood plain, wetland areas, ponds and obstructions in the Tributary 10 could occur. The survey sections allowed the decision to be made as to which obstructions should be modeled as detention areas using TR-20 and which ones should also be modeled using HEC-RAS in order to calibrate the TR-20 model. Because the surveys indicated that so many of the obstructions created detention areas, most of them were modeled as reservoirs in the TR-20 model. Only an area for one tributary was modeled using the HEC-RAS model to calibrate TR-20. That was the most westerly tributary from its junction with the mainstream channel upstream to just north of U.S. Route 11. Analysis from the HEC-RAS model was used to adjust the elevation versus discharge inputs for both the reach-routing sections and the reservoir routing tables for this section of the channel. The joint headwaters area of Kinney Run and Tributary # 10 was modeled to determine how the discharge was divided between the two watersheds. The Kinney Run sub-watersheds are included as part of the Tributary # 10 model discharge by using the divert routine in TR-20. The existing-conditions TR-20 model was run and calibrated by use of the HEC-RAS model and FEMA report. The calibrated model was then run for future development conditions. Due to the pressure to fill and develop many of the stormwater detention areas within the watershed, the model was run with fill placed in some of the detention and wetland areas. However no fill was placed within the designated floodway or within 15.24 meters (50 feet) of the top of a stream bank where there was not a designated floodway. Tributary # 10 Analysis Results The peak discharges for various locations and conditions were analyzed. The conditions analyzed were (1) Existing Conditions (2) Future Build-out Condition without Detention Area Fill (3) Existing Conditions with Detention Area Fill and (4) the Future Build-out with Detention Area Filling. Table 4 provides the results of the analysis. Their locations within the watershed are identified on Figure 2 The area between Central Road and Shaffer Hollow Road that acts as an unrecognized impoundment area controlled the existing conditions 100-year frequency discharge so that it did not overtop Shaffer Hollow Road. This greatly reduced the downstream peak discharge from the upstream area from 4.06 cubic meters per second (145 cubic feet per second) to 0.132 cubic meters per second (4.7 cubic feet per second). If the area is developed and the detention area filled, the 10-year and higher frequency storms would overtop Shaffer Hollow Road and create additional flooding problems for the houses on the eastern side of the roadway. The westerly tributary to Tributary #10 TR-20 valley routing discharges and discharge elevations both north and south of its intersection with U.S. Route 11 were adjusted based upon the HEC-RAS results. U.S. Route 11 and the Railroad fill adjacent to it, when evaluated by the HEC-RAS model, were found to act more like a stormwater detention structure for lower frequency storms. The structure discharge input values for storage versus discharge in the TR-20 model were adjusted to reflect the results of the HEC-RAS analysis. The future development with flood plain fills would increase the peak discharge at this location from 17.556 cubic meters per second (627 cubic feet per second) for the 100-year frequency storm to 19.142 cubic meters per second (676 cubic feet per second). This is a 7.8% increase in peak discharge. The increased discharge at this location was the result of development within the watershed and not filling of the flood plain.

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When comparing the three alternatives with the existing conditions at Ridge Street for the 2 through 100-year storms, the flood plain filling had a much greater impact on increasing the peak discharge than development alone. Filling the flood plain resulted in a 92.3% increase in the 2-year discharge and a 68.5% increase in the 100-year discharge. When comparing the three alternatives with the existing conditions at Edgar Avenue at the mouth of Tributary #10 for the 2 through 100-year storms, the flood plain filling again had a much greater impact on the peak discharge than development alone. Filling the flood plain resulted in a 4.5% increase in the 2-year discharge, from 3.136 to 3.276 cubic meters per second (112 to 117 cubic feet per second), and an 81.3% increase in the 100-year discharge, from 20.692 to 37.52 cubic meters per second (739 to 1340 cubic feet per second). Although the 2-year frequency storm discharge was not significantly increased, the 5 through 100-year storms were subject to a major increase as a result of filling flood plain areas, with land development having minor impacts when compared to existing conditions. The existing conditions model discharges were compared with the FEMA discharges at U.S. Route 11 and at the mouth. The discharge at U.S. Route 11 for the FEMA study, corrected for difference in drainage areas between the FEMA study and the County GIS, and the TR-20 analysis correlated well for the 10, 50 and 100-year frequency storms (Table 5). When the existing condition discharges at the mouth were compared, there was very poor correlation (Table 5). The FEMA study did not try to account for natural and man-made stormwater detention areas within the river flood plain. When these detention areas are accounted for in the modeling, they provide a major reduction of the peak discharges. Even when the flood plain is filled to legal limits, there is still significant stormwater detention within the watershed that requires that detention be considered in modeling the watershed. Conclusions Accelerated erosion of upland stream channels tributaries has partially or completely filled in some channels at the Susquehanna River flood plain interface. In some cases, such as the joint headwaters area of Kinney Run and Tributary #10, the stream channel no longer exists. Areas where channels are filled in are either (1) where they were previous drained for agricultural purposes reverting to wetlands or (2) creating new wetland areas. The flatter-graded channel reaches within both watersheds are accumulating sediment that would pass through them if they had steeper gradients and they are slowly loosing their conveyance capacity. The existing natural and created stormwater detention areas in both watersheds have an important impact on downstream stormwater discharges. The normal procedures for designing stormwater detention or retention facilities due to increases in impervious areas will not result in control of increases in downstream discharges on these detention areas. Except where these areas have been zoned as a Flood Overlay District in Scott Township, there are no restrictions for placement of fill or buildings within these detention areas. Some of the areas are wetlands, which would require State, and Federal permits in order to develop them. However, the proximity to infrastructure and economic benefits for developing these areas has resulted in property owners and developers seeking permits to develop these areas by providing for wetlands mitigation at other sites. For the Flood Overlay District areas only, a property owner can propose development as long as the first floor of the buildings are above the 100-year flood level. This leads to filling of these detention areas and until now an unrecognized increase in downstream peak discharges. These areas need to be protected from future filling by implementing additional zoning controls.

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However, the owners of the existing natural or created detention areas may consider this as a taking away their right to use their land and could seek compensation through the legal system. The common headwater areas for Kinney Run and Tributary #10 that are not recognized as 100-year flood plain on the FEMA Flood insurance maps need to be added to the maps. At the same time, the FEMA study for Tributary #10 should be revised based upon the TR-20 discharge data for the mouth. The undersized culverts and manmade obstructions within the watershed create not only the problem of local flooding; but, also, benefits by detaining stormwater and reducing downstream peak discharges. As culverts are replaced with larger ones, an analysis should be made of the effect this culvert replacement may have for increasing downstream discharges. Because of the complexity of the watersheds, any culvert or bridge replacement should be done only after analyzing both the changes to peak discharge and the potential for detrimental changes to both the upstream and downstream flood level elevations. A modeling of the culvert would be required with both a hydrology model for changes in peak discharge due to increase or decrease in stormwater detention and a hydraulics model for water surface elevations changes. The difference in the FEMA studies for the Town of Bloomsburg and Scott Township for peak discharge for Kinney Run indicates that both studies are correct. The Bloomsburg study is based only upon the discharge to the river, which is controlled by the 1800-millimeter (72-inch) diameter stream enclosure in the Town Park and the 1500-millimeter (60-inch) diameter Catherine Street culvert. The Bloomsburg FEMA study did not provide any discharges upstream of the mouth. The Scott Township study included the entire Kinney Run drainage area to that location. Due to the watershed characteristics of Kinney Run and Tributary #10, especially in their joint flood plain with the Susquehanna River, field survey of valley cross-sections and their use in the TR-20 model was necessary to provide accurate evaluation of the stormwater discharges. It was anticipated at the start of the study that there were a number of stormwater detention areas within both watersheds. However, the extent that some roadways and the railroad would influence stormwater detention was not fully apparent until the surveys were provided. For example, the complexity of the backwater problem created by Catherine Street in Bloomsburg would not have been recognized and properly analyzed, nor would the divided flow condition at the joint headwaters of Kinney Run and Tributary No. 10 or the airport diversion structure been properly analyzed.

Samuel E. Young, P. E.

Larson Design Group, Inc. 702 Sawmill Road, Suite 106 Bloomsburg, PA 17815

570-387-6680

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TABLE 1 Kinney Run Critical Location Descriptions Map Symbol Label Description D-1 Diversion #1 Sediment clogged channel and wetlands where upslope portion of Kinney Run stormwater discharge is partially diverted to Tributary No. 10 Scott Township

O-1 Obstruction #1 Central Road culvert and road fill create a stormwater impoundment. Overflow elevation at Central and Shaffer Hollow Road in Tributary No. 10 watershed Scott Township is 0.03 meters (0.1 feet) in elevation.

SWS-1 Stormwater Storage #1 Espy Bog is an excavated pond that provides stormwater detention due to wide wooded outlet to valley and stream with only 0.002 meters / meter gradient.

SWS-2 Stormwater Storage #2 Wide flood plain from Espy Bog to Bloomsburg / Scott Township line that provides a large volume of stormwater storage.

O-2 Obstruction #2 Walnut Street 1200-millimeter (48-inch) diameter culvert is an undersized culvert that causes road overtopping 3 to 4 times a year.

D-2 Diversion #2 Diversion structure near the Bloomsburg Recycling Center designed to divert excess flow from Kinney Run directly to the Susquehanna River and reduce downstream flooding on Kinney Run in Bloomsburg.

O-3 Obstruction #3 Recycling center access road and 1500 mm (60-inch) diameter culvert installed since the diversion structure was constructed. Affects function of diversion structure by creating backwater.

O-4 Obstruction #4 Catherine Street fill and 1500 mm (60-inch) diameter culvert creates backwater problems at the Recycling Access Road culvert and Diversion #2.

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TABLE 2 Kinney Run Existing Conditions Versus Future Conditions Comparison Discharge for:

1. Existing Conditions (Ex. Cond) 2. Build-out Condition (B.O. Cond) 3. Flood Plain Fill Condition Only 4. Build-out with Fill Condition (B.O. Fill Cond) Storm Flood Plain Frequency Ex. Cond B.O. Cond Fill Cond Only B.O. Fill Cond Years m3 / sec CFS m3 / sec CFS m3 / sec CFS m3 / sec CFS

Central Road (O-1) 2 0.595 (21) 0.793 (28) 0.595 (21) 0.764 (27) 5 0.906 (32) 0.991 (35) 0.963 (34) 1.076 (38) 10 1.161 (41) 1.189 (42) 1.218 (43) 1.756 (62) 25 1.189 (42) 1.218 (43) 2.180 (77) 2.633 (93) 50 1.699 (60) 2.095 (74) 3.002 (106) 3.681 (130) 100 2.322 (82) 2.690 (95) 3.851 (136) 4.474 (158)

Route 11 @ Street to Esby Bog 2 2.067 (73) 2.322 (82) 2.067 (73) 2.322 (82) 5 3.511 (124) 3.908 (138) 3.540 (125) 4.021 (142) 10 5.408 (191) 5.663 (200) 5.610 (198) 5.862 (207) 25 6.314 (223) 6.683 (236) 6.540 (231) 6.881 (243) 50 7.447 (263) 7.872 (278) 7.790 (275) 8.212 (290) 100 8.580 (303) 9.033 (319) 8.860 (313) 9.316 (329)

Sherwood Village East Development (SWS-2) 2 9.118 (322) 10.958 (387) 9.340 (330) 11.157 (394) 5 16.197 (572) 18.661 (659) 16.540 (584) 19.057 (673) 10 24.494 (865) 28.430 (1004) 25.600 (904) 29.138 (1029) 25 30.299 (1070) 34.376 (1214) 31.090 (1098) 35.112 (1240) 50 36.896 (1303) 41.597 (1469) 37.830 (1336) 42.503 (1501) 100 42.532 (1502) 48.053 (1697) 43.580 (1539) 48.761 (1722)

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TABLE 2 continued Kinney Run Existing Conditions Versus Future Conditions Storm Flood Plain Frequency Ex. Cond B.O. Cond Fill Cond Only B.O. Fill Cond Years m3 / sec CFS m3 / sec CFS m3 / sec CFS m3 / sec CFS

Bloomsburg / Scott Township Boundary 2 5.918 (209) 6.654 (235) 7.480 (264) 8.552 (302) 5 10.930 (386) 12.204 (431) 13.790 (487) 15.631 (552) 10 17.386 (614) 19.708 (696) 22.170 (783) 24.777 (875) 25 21.945 (775) 24.126 (852) 27.180 (960) 30.270 (1069) 50 26.957 (952) 29.534 (1043) 33.380 (1179) 37.010 (1307) 100 31.630 (1117) 34.376 (1214) 38.710 (1367) 42.758 (1510)

Diversion Structure toward Town Park (D-2) 2 1.161 (41) 1.274 (45) 1.420 (50) 1.586 (56) 5 1.954 (69) 2.124 (75) 2.410 (85) 2.662 (94) 10 2.917 (103) 3.143 (111) 3.880 (137) 4.332 (153) 25 3.794 (134) 3.511 (124) 4.900 (173) 5.040 (178) 50 4.814 (170) 4.332 (153) 5.190 (183) 5.324 (188) 100 5.069 (179) 5.097 (180) 5.580 (197) 5.918 (209)

Diversion Structure toward Airport Runway (D-2) 2 5.154 (182) 5.833 (206) 6.680 (236) 7.645 (270) 5 9.741 (344) 10.789 (381) 12.570 (444) 14.102 (498) 10 15.772 (559) 17.754 (627) 20.190 (713) 22.200 (784) 25 19.793 (699) 22.030 (778) 24.640 (870) 27.325 (965) 50 24.211 (855) 26.900 (950) 31.230 (1103) 34.291 (1211) 100 28.656 (1012) 31.290 (1105) 36.700 (1296) 39.983 (1412)

Route 487 @ Airport 2 11.298 (399) 11.270 (398) 11.330 (400) 11.185 (395) 5 16.622 (587) 16.367 (578) 16.740 (591) 16.551 (584) 10 23.021 (813) 22.625 (799) 23.190 (819) 22.965 (811) 25 24.749 (874) 26.193 (925) 26.870 (949) 26.589 (939) 50 31.063 (1097) 30.497 (1077) 31.320 (1106) 31.120 (1099) 100 34.574 (1221) 34.121 (1205) 33.890 (1197) 33.272 (1175)

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TABLE 2 continued Kinney Run Existing Conditions Versus Future Conditions Storm Flood Plain Frequency Ex. Cond B.O. Cond Fill Cond Only B.O. Fill Cond Years m3 / sec CFS m3 / sec CFS m3 / sec CFS m3 / sec CFS

Catherine Street (O-4) 2 5.040 (178) 5.125 (181) 5.070 (179) 5.125 (181) 5 5.975 (211) 6.031 (213) 6.060 (214) 6.173 (218) 10 7.107 (251) 7.136 (252) 7.220 (255) 7.334 (259) 25 7.645 (270) 7.645 (270) 7.840 (277) 7.957 (281) 50 8.325 (294) 8.268 (292) 8.410 (297) 8.467 (299) 100 8.665 (306) 8.693 (307) 8.690 (307) 8.750 (309)

Town Park Pipe to River 2 4.247 (150) 4.361 (154) 4.300 (152) 4.417 (156) 5 5.437 (192) 5.493 (194) 5.550 (196) 5.635 (199) 10 6.598 (233) 6.683 (236) 6.740 (238) 6.824 (241) 25 7.277 (257) 7.277 (257) 7.480 (264) 7.560 (267) 50 8.183 (289) 8.098 (286) 8.300 (293) 8.353 (295) 100 8.665 (306) 8.665 (306) 8.690 (307) 8.750 (309)

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TABLE 3 Tributary #10 Critical Location Descriptions Map Symbol Label Description D-1 Diversion #1 Sediment clogged channel and wetlands where upslope portion of Kinney Run stormwater discharge is diverted to Tributary No. 10 Scott Township SWS-1 Stormwater Storage #1 Private access road northwest corner of Wal-Mart property with 380 millimeter (15-inch) diameter culvert that acts as control structure for storing stormwater runoff. SWS-2 Stormwater Storage #2 Shaffer Hollow Road fill acts as a dam to create a stormwater impoundment. Outflow is controlled by a 380-millimeter (15-inch) diameter clay tile pipe installed as a public works project in the 1930’s. Tile pipe is 457 meters (1500 feet) long and in poor condition. Shaffer Hollow Road overflow elevation is within 0.03 meters (0.1-feet) of overflow elevation for Kinney Run @ Central Road. SWS-3 Stormwater Storage #3 The area between Bissetts Lane and Ridge Street. Outflow is controlled by a 1200-millimeter (48- inch) diameter pipe and a narrow road overflow area. SWS-4 Stormwater Storage #4 Carrol Park Drive roadway was constructed to create one f two ponds within the development. It has a 900-millimeter (36-inch) culvert, which acts as the principal spillway. Beaver regularly obstruct the pipe and create a larger pond that extends to just downstream of Ridge Road. This further reduces the capacity of the Ridge Road culverts. SWS-5 Stormwater Storage #5 Edger Avenue Road fill and 1727 millimeter wide by 1092 millimeter high (63-inch by 43-inch) diameter culvert.

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TABLE 3 continued Tributary #10 Critical Location Descriptions Map Symbol Label Description O-1 Obstruction #1 Obstruction #1 is a 244-meter (800-feet) long stream enclosure. It starts out as a 1372-millimeter (54-inch) diameter pipe but outlet as an 864- millimeter (34-inch) diameter pipe. The channel upstream from the entrance has considerable floatable debris, much of which is deposited on the banks by local residents. The entrance of the stream enclosure has a trash guard, which is plugged to one half the opening height. One resident has stated that periodically holes open in the ground above the pipe indicating problems with the structural integrity of the conduit.

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TABLE 4 Tributary No. 10 Scott Township Existing Conditions Versus Future Conditions Future Conditions:

1. Land Built Out (Agricultural & Woodland to "C" Shape) 2. Flood Plain Filled 3. Flood Plain Filled / Built Out

Storm Future Conditions Frequency Existing 1 2 3 Years CMS CFS CMS CFL CMS CFS CMS CFS

Shaffer Hollow Road ( SWS-2) 2 0.064 (3) 0.084 (3) 0.112 (4) 0.112 (4) 5 0.112 (4) 0.112 (4) 0.140 (5) 0.224 (8) 10 0.112 (4) 0.112 (4) 0.480 (17) 0.560 (20) 25 0.112 (4) 0.112 (4) 0.650 (23) 0.784 (28) 50 0.140 (5) 0.140 (5) 1.020 (36) 1.680 (60) 100 0.140 (5) 0.140 (5) 2.240 (79) 3.276 (117)

U.S. Route 11 @ Dairy Queen 2 2.408 (86) 2.548 (91) 2.408 (86) 2.464 (88) 5 4.480 (160) 5.012 (179) 4.480 (160) 5.012 (179) 10 8.848 (316) 10.668 (381) 8.820 (315) 10.640 (380) 25 12.264 (438) 13.048 (466) 12.236 (437) 13.020 (465) 50 15.120 (540) 16.156 (577) 15.092 (539) 16.128 (576) 100 17.556 (627) 19.142 (676) 17.528 (626) 19.142 (676)

U.S. Route 11 Near Bissetts Lane 2 3.500 (125) 3.332 (119) 3.500 (125) 3.332 (119) 5 6.048 (216) 5.964 (213) 6.048 (216) 5.964 (213) 10 9.268 (331) 9.324 (333) 9.268 (331) 9.324 (333) 25 11.172 (399) 11.312 (404) 11.172 (399) 11.312 (404) 50 13.468 (481) 13.776 (492) 13.468 (481) 13.776 (492) 100 15.456 (552) 15.876 (567) 15.456 (552) 15.876 (567)

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TABLE 4 continued Tributary No. 10 Scott Township Existing Conditions Versus Future Conditions Ridge Street (SWS-3) 2 1.820 (65) 1.680 (60) 3.500 (125) 3.332 (119) 5 3.332 (119) 3.164 (113) 6.636 (237) 6.524 (233) 10 5.740 (205) 5.516 (197) 10.528 (376) 10.640 (380) 25 7.280 (260) 7.056 (252) 12.852 (459) 13.048 (466) 50 9.156 (327) 8.960 (320) 15.736 (562) 15.960 (570) 100 10.752 (384) 10.584 (378) 18.116 (647) 18.480 (660)

Edgar Avenue (SWS-5) 2 3.136 (112) 3.108 (111) 3.276 (117) 3.248 (116) 5 5.376 (192) 5.628 (201) 8.148 (291) 8.036 (287) 10 9.856 (352) 10.892 (389) 17.808 (636) 17.556 (627) 25 13.664 (488) 14.308 (511) 24.276 (867) 23.968 (856) 50 17.528 (626) 18.228 (651) 31.584 (1128) 31.584 (1128) 100 20.692 (739) 21.560 (770) 37.520 (1340) 37.940 (1355)

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TABLE 5 Tributary No. 10 TR-20 Versus FEMA

Discharge Storm Frequency TR-20 Discharge FEMA Report Revised (1) Years CMS (CFS) CMS (CFS) CMS (CFS)

U.S. Route 11 @ Dairy Queen 10 8.950 (316) 6.800 (240) (282) 50 15.290 (540) 13.030 (74) (541) 100 17.750 (627) 16.710 (590) (737)

At Mouth 10 11.270 (398) 29.170 (1030) 50 19.080 (674) 50.970 (1800) 100 22.280 (787) 62.580 (2210)

(1) Note: FEMA Discharge corrected for Discrepancy in Drainage area between FEMA Study and Columbia County GIS. FEMA Study D.A. = 0.46 square miles and Columbia County GIS D.A. = 0.58 square miles as reduced for 0.13 square miles controlled by SWS-2 system. qr = q(0.58/0.46) 0.7

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D-1

O-1

Kinney’s Run

SWS--1

SWS-2

O-2

D-2 O-3

O-4

FIGURE 1 KINNEY RUN WATERSHED Page 1

Tributary No. 10 D-1 SWS-3 SWS-1 SWS-2

SWS-4

O-1 SWS-5

FIGURE 2 TRIBUTARY NO. 10 Page 2

List of References

1. TR-20 Project Formulation Hydrology U.S. Department of Agriculture Natural Resource Conservation Service May 1983

2. Hydrologic Engineering Center – River Analysis System US Army Corps of Engineers Hydrologic Engineering Center 609 Second Street Davis, CA 95616-4687

3. Flood Insurance Studies Town of Bloomsburg, Columbia County, Pennsylvania May 1, 1980 420339

4. Flood Insurance Studies Township of Scott, Columbia County, Pennsylvania March 2, 1981 421004

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