Economic Development

In its continuing efforts to promote economic and industrial development within Bamberg County and to raise the standards of living of its citizens, County officials commissioned this Water and Wastewater Regionalization Study to be performed in order to assess the potential impacts and costs associated with creating a regional public water system with the five (5) existing public water service purveyors. It would stand to reason that Bamberg County should be able to allocate a larger quantity and a higher quality of water to the existing and future commercial and industrial customers in order to meet their needs and to stimulate additional economic growth by pooling their collective resources.

In order to evaluate the capacity of a regionalized system, the capacity of each system must be evaluated and then analyzed compositely to assess the need for additional supply, storage, and/or distribution facilities. Water supply capacities have been assessed based on the SCDHEC SPDWR in Section 2.0 of this report. Current water consumption data and projected water consumption data provided for the assessment of water supply capacity in a potential regionalized, or county-wide, system is depicted in Table 5.1.1-1. It should be noted that the City of Denmark, at present, relies on the interconnection with the BBPW to supplement its capacity in order to meet its customers’ current water demand.

Table 5.1.1-1 Total Supply Capacity and Demands

Note: 400,000 gallons of BBPW capacity not included in total are included
in the City of Denmark Capacity

The population density map, shown in Exhibit AA, clearly depicts that the highest volume and largest number of potential customers is located near the City of Denmark and the City of Bamberg. Moreover, the greatest region for potential economic and industrial development in Bamberg County would naturally be located in the City of Denmark, in the City of Bamberg, or along the 6.5-mile U.S. Highway 78 corridor between them. If the existing water supply resources in Bamberg County were to be regionalized by interconnections, no additional supply sources would be required to meet current or anticipated water usage for the study period.

A key component of determining the quality of raw groundwater that may be pumped from deep wells is to identify the underground aquifers from which the groundwater is being drawn. By determining the approximate ground elevation, drilling depth, screen locations, and the geographic location of the well, determination of the most desirable aquifer(s) can take place. Different aquifers tend to have different water characteristics as well as different geographical locations and elevation ranges. A geological cross section A-A’ from Williston through Denmark and into Ehrhardt is depicted in Exhibits AB and AC. Also shown are the ground surface elevations along with approximate geographical locations and elevations of known aquifers with respect to Mean Sea Level (MSL). Furthermore, Appendix Q includes an aquifer diagram of the highest water elevation and the approximate thicknesses of the known and notable aquifer formations within Bamberg County. Based on this information and groundwater well data obtained from the SCDNR records, a graph depicting the surface elevation and all screening locations in groundwater wells in Bamberg County is presented in Appendix T. A summarized version of important parameters to be evaluated when considering aquifers is depicted in Table 5.1.2-1.

Table 5.1.2-1 Well and Aquifer Data

Note:
BBPW Well No.3A abandoned and BBPW’s Well No.3 is SCDNR's Well No.3

It is important to note that groundwater hydrology is very complex, and it is often difficult to predict the quality of groundwater in a region due to unforeseen parameters. Additionally, it is possible for the quality of groundwater within an aquifer to change. The known groundwater aquifers within Bamberg County are layered according to depth as follows: Cooper, Congaree, Santee, Black Mingo, Peedee, Black Creek, Middendorf and Cape Fear. The upper most aquifer system, known as the Floridian aquifer system, consists of the Cooper, Congaree, and Santee Formations. The lower most aquifer system, located within the coastal plain is known as the Cretaceous aquifer system and consists of the PeeDee, Black Creek, Middendorf, and Cape Fear Formations. The SCDNR maintains records of general groundwater characteristics from each aquifer and these records should be examined prior to designing any new wells within Bamberg County.

According to SCDHEC’s SPDWR, elevated water storage tanks shall be provided for systems serving more than 300 customers and they shall be sized to provide for peak hourly demands plus minimum fire flow requirements for not less than two (2) hours. The peak hourly demand (PHD) is based on 2.7 times the average daily demand. Minimum fire demand requirements are dependant upon the nature of the structures and facilities in need of protection, but in no case shall the demands be less than 500 GPM. On occasion, industrial fire flow storage requirements may necessitate four (4) hours of storage with demands of 1,500 GPM or greater. In the evaluation of the existing and future systems, the actual elevated storage provided by each tank is compared with the demand predicted by the computer simulation for that tank during peak hour demands within the specified distribution network. The precise language of the SPDWR reads as follows:

The distribution storage also shall be designed to supply one half the maximum daily demands in a 24-hour period.  The maximum daily demand is typically assumed to be 1.5 times the average daily demand.

It is recommended that all regions of Bamberg County meet existing requirements within their systems based on the current demands that are tabulated in Table 5.2-1. The average daily demand is assumed to be the usage rate that corresponds to the SCDHEC’s sanitary survey’s daily production records.

Table 5.2-1
Existing Elevated Storage Volume Evaluation

Both the Town of Ehrhardt and the City of Denmark need additional elevated storage volume to meet SCDHEC’s fire protection requirements based on current demands. Due to structural deficiencies, age of the tank, and two (2) independently conducted PER’s for the Town of Ehrhardt in recent years, it was strongly recommended that the existing elevated storage tank be replaced. One (1) of the PER’s recommended that Ehrhardt’s existing tank be replaced with a 100,000-gallon elevated storage tank. A regional system had previously been recommended and proposed between the Towns of Olar and Govan which would include a new 100,000-gallon elevated storage tank. If the Town of Ehrhardt was to construct a new 100,000-gallon elevated storage tank as previously recommended and assuming that the Olar-Govan interconnection was constructed as recommended by its 2006 PER, these systems would meet SCDHEC requirements. A list of all active elevated storage tanks has been compiled to assess their ability to support a regionalized system. All active and proposed elevated storage tanks included in Bamberg County’s public water systems are in Table 5.2-2.

Table 5.2-2
Elevated Storage for Potential Regional System

It is important to note that if tanks within regions of surplus cannot convey their surplus storage volumes to the deficient regions due to the elevation differences, then booster pumping and/or additional elevated storage facilities may be required to support a regionalized system. An evaluation of the projected and anticipated demands for 2010 within Bamberg County for the purpose of ensuring that the systems would have the required elevated storage volumes available is presented in Table 5.2-3.

Table 5.2-3 Evaluation of Elevated Storage Tanks

Based on the anticipated daily demands, all areas of a regionalized system, except for the City of Denmark, will have sufficiency capacity to meet SCDHEC requirements on an individual basis. Based on projected demands, a potential regionalized water system would have surplus elevated storage capacity to meet SCDHEC’s requirements through the study period. The elevated storage facilities within the City of Denmark feature elevations above all other storage facilities within Bamberg County. This being the case, some additional booster pumping may be required to ensure that the elevated storage tanks within the City of Denmark can be filled by other suppliers within a regionalized water system. Additionally, some regions may require additional elevated storage to meet the localized demands of industrial customers who may wish to locate within Bamberg County. It is suggested that any new elevated storage tanks within the Denmark distribution system, the BBPW distribution system, and the Bamberg County Airport Industrial Park be sized and elevated to ensure that all fire hydrants located between the City of Denmark and the City of Bamberg along U.S. Highway 78 can supply at least 1,000 GPM for industrial fire protection needs.

Under average daily demand conditions, the normal working pressure in distribution systems should be approximately sixty (60) Pounds per Square Inch (PSI). Additionally, with peak hourly demands simulated as 2.7 times average daily demands, minimum residual pressures in the distribution systems during peak demand periods can not be less than twenty-five (25) PSI. During periods of peak demand with additional fire flow demands, the minimum residual pressure must not be less than twenty (20) PSI.

A simplified hydraulic model of a potential regionalized water distribution system was used to model the potential interconnection mains and their effects within the existing systems. The model calculations are based on the interconnecting main conveying water supply from one region’s elevated tank to the next. In conjunction with conveying water supply from one tank to another, interconnecting mains are preliminarily sized to convey the associated fire protection demands of 500 GPM at any proposed hydrant. Additionally, the interconnecting mains are preliminarily sized to convey a flushing flow with a velocity of at least two and half (2 ½) Feet Per Second (FPS).

This Feasibility Study assumes that the Town of Ehrhardt’s water improvements and the water system interconnection between the Towns of Olar and Govan will be constructed. The Town of Ehrhardt has already obtained and secured the majority of the funding required to replace virtually all of its aging water distribution system and to replace its existing 75,000-gallon elevated water storage tank with a new 100,000-gallon elevated storage tank. The Towns of Olar and Govan have already completed a PER to replace a large portion of their water distribution systems and interconnect their systems, and the PER has been preliminary approved by the SCDHEC. The Towns are currently seeking additional funds to offset the cost associated with the proposed improvements and interconnection.

It is important to note that the BBPW can produce about seventy-five percent (75%) of the finished water supply capacity within the potential regional system. The City of Denmark, on the other hand, is not currently able to produce the required volume of water to meet its daily customer demands without wholesale purchase of water from the BBPW. Utilizing the surplus supply capacity of the BBPW to supply the City Denmark, the Town of Olar, the Town of Govan, and the Town of Ehrhardt would allow for potential industries to locate their facilities in these portions of Bamberg County. With the significant investments made by the BBPW in the last few years with its Well No. 8, Well No. 9, and their associated treatment facilities, the logical source of water supply in Bamberg County at present would involve a continued reliance on groundwater. This being the case, the water supply options in Bamberg County can be met with each water purveyor continuing to independently operate and maintain their own water system (except in the case of the City of Denmark needing to supplement its supply from the BBPW) or combining their resources by regionalizing water service. Some water purveyors have been plagued with unforeseen events that have affected their ability to supply clean water. It is also important to note that the average useful life of most groundwater wells is approximately thirty (30) to forty (40) years. By regionalizing water service, the supply resources can be more effectively shared and utilized for the overall welfare of the County. Even in regionalization, however, there will be a continuing need for water system maintenance, repairs, and replacement activities. With the regionalization of the water systems, it is proposed that the four (4) major regions of Bamberg County would be interconnected along the major highways. These interconnections should increase the potential for economic and industrial development along the major highways. The map presented in Exhibit AD illustrates the approximate ground elevation near the center of each municipality and the direct distances between these municipalities. Additionally, a topographic map which depicts elevations throughout Bamberg County is presented in Exhibit AE. The enlarged versions of Exhibits AD and AE can be found in Appendix U and Appendix R respectfully.

As depicted in the proposed improvements map, not all of the potential interconnections may need to be made in order to regionalize water service within Bamberg County. A total of six (6) interconnections are initially recommended along major highways within Bamberg County. The interconnection between BBPW and the City of Denmark has been constructed and currently allows the BBPW to supply the Bamberg County Airport Industrial Park’s elevated storage tank and the City of Denmark. The potential interconnection between the Town of Ehrhardt and the Town of Govan is not currently viewed as economically feasible nor essential for the regionalized supply of water. Both of these Towns have existing and proposed wells which will supply water to their systems in the event that water cannot be supplied from the BBPW. Moreover, the interconnection between the BBPW and the interconnected Olar/Govan system is at least three (3) miles shorter than the potential Ehrhardt-Olar interconnection. This being the case, only three (3) of the potential regional interconnections would be viewed as water service regionalization projects for the foreseeable future within Bamberg County and these are depicted in Exhibit AF. All three (3) interconnecting water mains have been preliminary sized based on the fire flow (minimum 500 GPM) or flushing flow to create a minimum of two and half (2½) FPS plus peak hour demand, whichever is greater. The first potential interconnection between the BBPW and Town of Ehrhardt, which will be called the Bamberg-Ehrhardt interconnection, must be sized such that water can be conveyed from the Rutland Street Tank in Bamberg to the proposed 100,000-gallon Ehrhardt Tank.

Exhibit AG depicts the direction of water distribution from the BBPW system to the Town of Ehrhardt. It is important to note that by constructing the three (3) proposed interconnections, public water service will be available to additional residents of Bamberg County. Based on a completed examination of aerial photographs of Bamberg County along the proposed interconnection routes, the number of potential residential customers that could be supplied water service is tabulated in Table 5.4-1. It should also be noted that the potential residential customer counts are based on aerial photographs from 2005. Additionally, it should be noted that the anticipated water demands projected in Section 4.3 of this report do not include projected demands associated with the addition of new residential customers along the proposed regional interconnection mains.

Table 5.4-1
Potential Additional Customers along Interconnection Mains

Preliminary sizing calculations associated with these interconnection mains are included in Exhibit AH. Additional calculations associated with the interconnection between the BBPW and the proposed Olar/Govan system, known as the Bamberg-Olar/Govan interconnection, and the interconnection between the City of Denmark and the proposed Olar/Govan system, known as the Denmark-Olar/Govan interconnection, can be found in Exhibits AI, AJ, AK, and AL, respectively.

A computer model of the water systems proposed to be interconnected in Bamberg County was developed to further evaluate the hydraulic performance of a proposed interconnected County-wide system. A database of the existing components and characteristics of the distribution systems within the County was prepared in the development of the model. This database was compiled using WaterCAD from the Haestad Methods Solution Center at Bentley Systems, Inc.

A simplified schematic of the water distribution systems in Bamberg County was developed to form a skeletal system of the major water mains connecting key storage and production facilities in the distribution networks. This map was used to develop the water model. Noted on the map are intersections of major highways for location reference, improvement project numbers on pipe segments, and nodal numbers from the model database. Elevated tanks, wells, and pump stations are also depicted on the map.

The computer model of the water system is comprised of nodes and pipe segments. Nodes are established at connections with other pipes, changes in pipe diameter, known specific water demands, high and low system elevations, and system interconnection points. The residential and commercial water demands for each system were distributed across the system’s existing service area. Known specific large industrial demands were assigned to a specific nodes based upon their location.

As a first step to computer modeling of a water system, databases describing the various attributes of the water system model are determined. This database was created in the WaterCAD environment and consists of the following:

• Junction node data including elevations and demands;
• Pipe segment data including diameter, length, and roughness coefficients;
• Well and pump station data including pump curves and static water levels in wells; and
• Storage facility data including volume and estimated tank height to overflow.

The elevated storage tanks are modeled as fixed grade nodes, a method of representing the locations of known water surface elevations. These levels can vary, as in the case of analyzing an extended period simulation.

The program selected for use with this project, WaterCAD, was used to analyze steady state flow conditions for the pipeline distribution network while operating in AutoCAD. Beyond providing solutions to steady state simulations, the program is also capable of extended period simulations involving varying tank levels and diurnal fluctuations in demands.

Hydraulic evaluations of a simplified version of an interconnected system in Bamberg County were performed to assess existing and future conditions for the provision of water service throughout the County. These hydraulic evaluations, coupled with the existing and future water demands, provide the means necessary to determine the system improvements and expansions that would be necessary to reasonably meet current and projected population growth and associated demands, pressure requirements, supply for fire demand requirements, and storage requirements. The water systems in the simplified model included the City of Denmark, the BBPW, the proposed interconnected Olar/Govan System, and the Town of Ehrhardt. This model was evaluated as if the interconnections were complete and the system was operating as a single system. The Water System Modeling Results are presented in Appendix S.

The hydraulic modeling of the potential regional system confirmed the initial sizing calculations associated with both domestic demands and supplying fire protection needs and to reasonably ensure the longevity of the potential interconnections of the systems. It is the intent of this report that the interconnected water mains could be completed either as individual projects or as one (1) large regionalization project. In the best interest of the citizens of Bamberg County, the initial phases of the regionalization process should be constructed in order to provide water service the largest number of potential new customers. The BBPW has approximately seventy-five percent (75%) of the finished water production capacity within the County. Accordingly, it is recommended that construction of interconnection mains should be extended from the BBPW to other water service purveyors. The first recommended interconnection would then be between the BBPW and the Town of Ehrhardt along U.S. Highway 601. Next, it is recommended that the interconnection between the BBPW and the proposed Olar/Govan water system along U.S. Highway 301 and along Govan Road (S-5-22) be constructed. The third recommended interconnection would involve interconnecting the City of Denmark with the proposed Olar/Govan water system along U.S. Highway 321.

The recommended regional interconnection main between the BBPW and the Town of Ehrhardt, would include approximately 66,500 linear feet from the intersection of U.S. Highway 601 (Broxton Bridge Road) and U.S. Highway 301 (Main Highway) near the City of Bamberg along U.S. Highway 601 to its intersection with State Highway (S-5-566). It is recommended that this interconnection be a fourteen inch (14”) main to convey the required flow from the BBPW to the Town of Ehrhardt. Additionally, approximately 1,500 linear feet of this interconnection would involve the crossing of Little Salkehatchie River and Lemon Creek. It is recommended that the associated river and creek crossing be directional drilled with High Density Polyethylene (HDPE) pipe. It is also recommended that this interconnection include approximately sixty-five (65) fire hydrants, and sixteen (16) valves. The overflow elevation of the BBPW’s elevated storage tanks are approximately forty-six feet (46’) higher than the overflow elevation of proposed 100,000-gallon elevated storage tank for the Town of Ehrhardt. The interconnection construction cost opinion is presented in Table 5.4.2-1.

Table 5.4.2-1
Bamberg-Ehrhardt Interconnection Main Construction Cost Opinion

The second recommended regional interconnection would connect the BBPW’s system with the proposed Olar/Govan system in the southwestern portion of the County. The proposed route of the recommended interconnection is along the U.S. Highway 301 (Main Highway) from its intersection with Log Branch Road (S-5-503) and then south along Ehrhardt Highway (S-5-22) from its intersection with U.S. Highway 301 (Main Highway). The main will connect to the proposed Olar/Govan system at the intersection of Ehrhardt Highway (S-5-22) and Govan Road (S-5-32). The proposed elevated storage in the proposed Olar/Govan system has an overflow elevation that will be approximately sixty-five feet (65’) higher than those within the BBPW’s system. The hydraulic modeling of the potential regional water system within Bamberg County indicated that the interconnecting main be at least ten (10) inch diameter and that a booster pump station also be constructed to supply adequate volumes of water to the proposed Olar/Govan system. It is estimated that approximately 61,000 linear feet of water main be required to interconnect the two (2) systems. This interconnection will also require a crossing of Lemon Creek. It is recommended that approximately 1,000 linear feet of HDPE pipe will be directionally drilled under Lemon Creek. Other recommendations include the construction of approximately sixty (60) fire hydrants and sixteen (16) gate valves. As previously noted, this interconnection would include a Booster Pumping Station which has only been conceptually planned during the course of this study. The Booster Pumping Station is recommended to be located approximately 10,000 linear feet north of the intersection of U.S. Highway 301 (Main Highway) and Voorhees Road (S-5-12). The construction cost opinion has been estimated for this interconnection is presented in Table 5.4.2-2.

Table 5.4.2-2
Bamberg-Olar/Govan Interconnection Main Construction Cost Opinion

The third recommended regional interconnection would connect the City of Denmark’s system located in the northwestern region of the County with the proposed Olar/Govan system in southwestern region of the County. The proposed interconnection would extend along U.S. Highway 321 (Carolina Highway) from its intersection with Road S-5-54 near Denmark to its intersection with Road S-5-392. It should be noted that the overflow elevation of the existing elevated storage tanks within the City of Denmark water system is approximately ten (10) feet higher than the proposed overflow elevation of the proposed tank in the Olar/Govan system. Hydraulic modeling of the potential regional water system within Bamberg County indicated that at least a ten-inch (10”) main would be required to provide for the adequate conveyance of water between the these systems. It is estimated that approximately 28,500 linear feet of water main would be required to interconnect the two (2) systems. Additionally, it is recommended that the interconnection between the City of Denmark and the proposed Olar/Govan water system be completed as one of the last phases of the regionalization. The construction cost opinion for this interconnection is presented in Table 5.4.2-3.

Table 5.4.2-3
Denmark-Olar/Govan Interconnection Construction Cost Opinion