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HomeMy WebLinkAboutAgenda - 08-04-1997 - 10a ORANGECOUNTY BOARD OF COMMISSIONERS ACTION AGENDA ITEM ABSTRACT Meeting Date: August 4, 1997 Action Agenda Item # /O-a SUBJECT: Sewer Service Expansion Options-Boone Mobile Home Park DEPARTMENT: County Manager PUBLIC HEARING: Yes X No ATTACHMENT(S): BUDGET AMENDMENT: Yes )( No County Engineer's report INFORMATION CONTACT: County Engineer Extension 2303 TELEPHONE NUMBERS: Hillsborough - 732-8181 Durham - 688-7331 Mebane - 227-2031 Chapel Hill - 967-9251/968-4501 PURPOSE: To present for the BOCC's information a report outlining the integration of strategies for providing Mobile Home sewer service to Boone Park with the existing master planned extension of sewer service to the Perry Hills area. BACKGROUND: In Februray 1997, the BOCC was approached by Mr. Ernie McBroom, the new owner of Boone Mobile Home Park, about failing septic systems serving the homes in the park and potential public health problems related to those failures. He requested that the BOCC allow him to construct a sewer collection system within the park to connect the collection system to the nearby Hancor sewer force main system. The BOCC directed staff to investigate the Boone Mobile Home Park situation and bring back a report and a recommendation to the Board. At the March 18`h meeting, staff presented a report and recommended that the BOCC deny permission to tap onto the Hancor force main. The BOCC narrowly supported the staff recommendation but directed the staff to look at other options for providing adequate sewer to Boone Mobile Home Park. County staff has since developed and evaluated three potential alternatives that could provide sewer for Boone Mobile Home Park. Alternate 1 involved the purchase of land containing suitable soils adjacent to or nearby the park and the installation of on-site waste treatment systems. Alternate 2 involved the construction of a force main sewer collector system that would serve the entire US 70 corridor between Boone Mobile Home Park and the western end of the Efland sewer system. Alternate 3 involved the construction of a combination gravity collector/force main w 2 led collector system which would serve the Perry Hills community and the US 70 corridor. It was initially believed that Alternatives 2 and 3 might, by virtue of alleviating widespread problems of on-site waste treatment inadequacy, qualify for state clean water loan and grant funds. It has been determined that Alternative 1 is not a realistic solution to the problems at Boone Mobile Home Park. It has also been determined that Alternatives 2 and 3 will not likely qualify for loan and grant funding but could be viable long term County sewer assessment projects. Those costs have been provided and illustrated in the attached engineer's report. RECOMMENDATION: The Manager recommends that the Board receive the engineer's report as information 3 MEMORANDUM TO: County Commissioners John Link, County Manager FROM: Paul Thames, PE, County Engineer DATE: July 28, 1997 SUBJECT: Report on expansion of the Efland Sewer System to serve Boone Mobile Home Park, US 70 west of Efland and Perry Hills community In February 1997, County staff and Mr. Ernie McBroom, the new owner of Boone Mobile Home Park, advised the BOCC that several of the individual septic systems serving some of the homes in the park were malfunctioning and represented at least a potential public health problem. Mr. McBroom indicated that he had effected system repairs as directed by the Orange County Environmental Health section but that the repairs were not expected to be sufficient to serve the park for the long term. Mr. McBroom asserted that there were only two economical options that would address the problem over the long term: 1) a sewer collection system could be constructed at the mobile home park and then the collection system could be tied into the existing and relatively nearby Hancor force main system; or 2)the mobile home park's residents who were dependent on the failing systems could be compelled to move elsewhere. Mr. McBroom requested that the BOCC allow him to connect the park to the Hancor force main. The BOCC directed County staff to evaluate Mr. McBroom's request and report back to the Board with its findings in March. At the March 186'meeting of the BOCC, staff presented its evaluation of the situation at Boone Mobile Home Park and of the related aspects of operating status of the Hancor force main system. On the basis of. a) existing and ongoing operational problems with the Hancor force main system; b)the County's tacit understanding with Hancor as to its sole use of the force main; and c)the County's general utility operation and planning criteria, staff recommended that Boone Mobile Home Park not be allowed to tap onto the Hancor force main. The BOCC narrowly supported the staff recommendation to deny the tap but directed staff to develop and evaluate waste treatment alternatives which could alleviate the problem at the mobile home park. Some of the potential alternatives mentioned at the BOCC meeting and subsequently examined included: 1) locating areas having soil suitable for on-site waste treatment systems in obtainable properties adjacent to Boone Mobile Home Park; 2)the expansion of the Efland sewer system west along Hwy 70 to serve not only Boone Mobile Home Park but also the residents of the area between Boone and the western end of the existing system; and 3) expansion of the Efland sewer system to provide sewer service not only to US 70/Boone mobile home park area but the entire Phase VI (US Hwy 70 west and the Perry Hills area) portion of the Efland sewer master plan. In each of these potential strategies, the goal was to provide economical sewer service to Boone Mobile Home park and perhaps to others in the vicinity needing or desiring sewer service. Each of the alternatives outlined above has now been evaluated to at least a preliminary level. Local on- site waste treatment, Alternative 1, can essentially be ruled out for two reasons; a)there is a preponderance of poor soils in areas immediately adjacent to Boone Mobile Home Park; and b)the cost 4 „ of acquiring a more distant site for the sole purpose of developing on-site sewer treatment is not , economically feasible. Alternatives 2 and 3 are both feasible as long term County sewer assessment projects. As for Alternative 2, the US 70 corridor contains approximately 65 existing residential and non- residential units(including the eleven at Boone Mobile Home Park) on 70 lots and parcels having frontage on US 70. Fifteen of those parcels are fairly large and contain a total of approximately 200 undeveloped acres. Counting the development potential of that acreage along with the existing smaller undeveloped lots, the estimated buildout for the US 70 corridor is approximately 250 units. The sewer flow which would be assumed to be generated by 250 residential units could be accommodated in a four inch diameter force main collector line. The estimated engineering/construction/contingency cost to construct the four inch force main collector and service lateral stub-outs that would be necessary to provide build-out level service for just the US 70 corridor as far as Boone Mobile Home Park is approximately $190,000. An assessment cost recovery process based on acreage, lot and front footage should provide for an average assessment of less than$1000 per unit at build-out. Each unit would also be subject to costs for individual on-site pump stations(approximately $3000 each), County tap-on fees (currently$600 per unit) and Town of Hillsborough capital facilities fees(currently $1200 for less than% acre or and $1600 per acre for more than% acre). Using these cost figures(and a$1000 assessment for constructing the collector), the Alternative 2 total initial sewer service cost for typical residential user on a one acre lot would be approximately $6200. The estimated cost of this strategy to Mr. McBroom for one large pump station serving eleven units would be approximately $40,000 or $3600 per unit. Alternative 3 would provide sewer service for approximately 200 existing units or 250 units at buildout in the Perry Hills area for a total of approximately 265 existing units and 500 units at buildout. The majority of the Perry Hills community would be served by 8" gravity collector sewers which would drain to a major pumping station located near the northwest corner of the community. A six inch force main, routed back through Perry Hills and Boone Mobile Home Park and along US 70 to the Efland sewer system, would be required to serve both the Perry Hills and US 70 areas. The properties in the US 70 corridor would tap this force main in a manner similar to that proposed for Alternative 2. The total cost of Alternative 3 is estimated at approximately $2.3 million. The differences between the types of sewer service(gravity versus force main) and the associated on- and off-site costs can be expected to complicate the assessment process for Alternative 3. On a simple per build-out unit basis, the assessment would total approximately $4600. However, the assessment could be structured such that it compensated for both the additional on-site costs to those units requiring individual pumping station and the far greater off-site costs associated with developing gravity sewer service. This compensation process could be set up such that gravity sewer customers would pay approximately $6000 in assessment cost, and force main customers would pay $3000 in assessment cost and$3000 for on-site pumping cost. Each customer would still be subject to the County's$600 tap-on fee and the Town's capital facilities fee. Under the compensating assessment strategy for Alternative 3, the total initial sewer service cost for typical residential user on a one acre lot would be approximately$8200. The estimated cost of this strategy to Mr. McBroom, again with one large pump station serving eleven units, would be approximately $62,000 or $5600 per unit. According to Environmental Health section records, the US 70 and Perry Hills area do not report abnormally high levels of septic system failure. It is possible, but unlikely, that the area does have high levels of septic system failures that go undetected or unreported. In the absence of substantiated evidence of serious septic system problems or similar potential public health implications, however, the V 5 , chances of obtaining grant funding for expansion of the sewer service to the area are virtually non- existent. Given the almost certain absence of grant funding, all sewer expansion costs that the County decides to recover must be recovered by either the assessment process alone or by the assessment process in combination with an increase in the existing sewer rates. There are a number of permutations to the alternatives outlined above that can be developed to reduce initial sewer expansion costs, provide sewer service only for the US 70 corridor and accommodate a future system expansion to serve the Perry Hills area. One such example would be to construct the 6" force main needed to serve Perry Hills and the US 70 corridor as far as Boone Mobile Home Park, leaving the Perry Hills collection and pumping system construction until a later date. Another option could consist of not constructing the sewer service stub- outs along US 70 (particularly those requiring boring under US 70)until they are actually called for. However, none of these permutations result in an actual reduction of ultimate costs. The costs can only be shifted in terms of when they are paid or who pays them. If I may provide additional information, please advise.