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HomeMy WebLinkAboutP-54-80 sLEE 4 CORPORATION OF THE TOWN OF NEWCASTLE PLANNING AND DEVELOPMENT DEPARTMENT D.N.SMITH,M.C.I.P.,Director HAMPTON,ONTARIO LOB 1.10 TEL. (416)263-2231 REPORT TO THE PLANNING AND DEVELOPMENT COMMITTEE MEETING OF MARCH 31, 1980. REPORT NO. : P-54-80 SUBJECT: Tyrone Hamlet Development Plan BACKGROUND: On March 3, 1980 a public meeting was held to discuss the re- vised development plan for the hamlet of Tyrone. At that meeting, proposed staging policies were also discussed, in addition to a possible revision to the Implementation section of the plan. As a result of that meeting, it was apparent that the major concerns were relative to the proposed lot sizes, and the proposed hamlet limits. Relative to these issues was a related concern respecting impacts of new develop- ment upon existing wells. COMMENTS: Staff have reviewed the concerns and issues raised, and feel that staff's proposed modifications as discussed at the public meeting, adequately address these matters. We stress the fact that the large lot size and contracted boundaries are intended to facilitate monitoring of growth and its impacts upon existing wells and soil conditions. P110.11 2 - As discussed, the proposed modifications would permit a degree of flexibility in both the lot sizes and the amount of growth, which could be permitted within the hamlet's presently proposed boundaries. Appendix 1 to this report, details the proposed revisions. It should also be noted that we are suggesting a change to Section 4.3 of the hamlet plan, consistent with recent comments received from Regional Council in respect of Newtonville. Both revisions have been incorporated within the text of the hamlet plan which is attached. We also attach comments submitted by a Tyrone resident in respect of local soil con- ditions. We note that each of the letters stress a need for detailed on site investigation prior to determining lot sizes. This approach is consistent with the intent of the Hamlet Development Plan and the Durham Regional Official Plan. The present requirements of the Durham Regional Official Plan, as reinforced by the proposed Hamlet Development Plan, clearly place the onus for such studies upon proponents of develop- ment. In respect of the hamlets boundaries, we again stress the fact that the Durham Regional Official Plan limits Tyrone to infilling and minor extensions to existing development. As a matter of fact, the plan presently proposes a growth of approximately 50%. This, in itself, may not be considered as minor. Similarly, this figure could be increased, without boundary adjustments, to 70% by a simple reduction in the lot size requirements from 0.5 ha (1.25 ac.) to 0. 3 ha (0. 75 ac.) , (see table attached as Appendix 2) . Such a reduction should not be considered in the absence of detailed on-site investigations. i 3 - Directly related to our rationalization of lot sizes are the concerns of residents about the impact of new development upon existing wells. In that regard, the plan specifically requires new development to be serviced by drilled wells drawing from deeper aquifers than existing wells. This, combined with the increased lot sizes, should eliminate any draw-down effects usually associated with concentrated development utilizing private wells . CONCLUSION: The presently proposed Hamlet Development Plan for Tyrone re- presents a realistic approach to permitting controlled growth within the hamlet. Further expansion should only be considered after detailed engineering studies for the area have been carried out and the new growth has been carefully monitored. Staging policies, currently being reviewed by Regional staff, will permit assimilation of new residences and facili- tate the required monitoring program. The plan should, therefore, be en- dorsed by Committee and forwarded to Regional Council for comment prior to local Council adoption. RECOMMENDATION: That the Planning and Development Committee recommend to Council the following: 1. That Report P-54-80 be received; and that 2. The Hamlet Development Plan for Tyrone, as revised, be forwarded to the Council of the Regional Municipality of Durham in accordance with Section 10.4.2.2 of the Durham Regional Official Plan; and that - 4 - 3. Planning Staff report back to the Planning and Development Committee at their first appropriate meeting following receipt of Regional comments. Respectfully submitted, dowk TTE:lb D. N. Smith, M.C.I.P. March 17, 1980 Director of Planning APPENDIX 1 Section 4.2 4.2 Notwithstanding any provision of this Plan to the contrary, applications for development within the hamlet shall be accompanied by a detailed engineering report based on test drilling which confirms: (i) An adequate supply of potable water and soil con- ditions satisfactory for the effective operation of a private waste disposal system; and (ii) An adequate separation between water table and septic tile fields. If after conducting the above investigation, evidence satisfactory to the Town of Newcastle and the Durham Health Unit, has been produced which indicates that a reduction in the minimum lot area requirement is warranted, Council may approve such a reduction only so far as the minimum lot size is not reduced to below 0.3 ha (0. 75 ac) . Upon receiving such approval, the applicant may submit a proposal based on this reduction, to the maximum number of lots permitted by this Plan. Prior to the balance of the site being developed, an amendment to the Hamlet Plan shall be required in order to adjust the maximum number of lots permitted and if necessary the staging of those lots. Section 4.3 4.3 In accordance with Section 10.4.2.6 of the Durham Regional Official Plan, Regional Council in co- operation with the Council of the Town of Newcastle and the Ministry of the Environment shall regulate growth in the Hamlet of Tyrone in order to preclude groundwater or private waste disposal system problems which might arise as a consequence of develop- ment. The regulation of future growth shall be based on the results of a groundwater monitoring program to be undertaken jointly by the Town of Newcastle and the Ministry of the Environment which will include. i) An appraisal of the continuing availability of groundwater supplies to the existing residents as well as any depletion of the groundwater aquifer which may be caused by new development or otherwise; and ii) A sampling of the quality of the groundwater supply with respect to any contamination. APPENDIX 2 v HAMLET OF TYRONE - Growth Alternatives Present Proposal Previous Proposal Min. Lot Size 0.5 ha 0. 3 ha 0.5 ha 0. 3 ha (1.25 ac) (0. 75 ac) Number of Lots per- 25 35 50 85 mitted Growth at 5 units per 5 yrs. 7 yrs. 10 yrs. 17 yrs . year % Increase over existing 50% 70% 100 % 170% 49 units It can be seen from the above table that the actual growth of the hamlet may be increased by a simple reduction in lot size to 0. 3 ha without the need to increase the physical limits of the hamlet. In this instance, based upon available information, we are proposing a 50% increase. If, through detailed on-site investigation, evidence is produced which would justify a reduction in lot size, then at that time development could proceed, subject to Council approval, to the permitted number of lots as presently designated, using a reduced lot size. In order to develop the additional lots which might be realized by reduced lot sizes, an amendment would be required in order to adjust the maximum number of lots indicated on the Plan. In this way, growth would proceed within the presently proposed limits but with a degree of flexi- bility. Further expansions to the hamlet boundaries would only be considered after development is substantially complete within present boundaries and only after careful consideration of environment, soil and groundwater conditions. ta+l! The Trow Group Limited OSHAWA BRANCH CONSULTING 865 NELSON STREET, OSHAWA, ONTARIO ENGINEERS (416) 571-2811 L 11-i 5 N 7 Project: 0 153 February 28, 1980 Mr. Q. Homing LPLANNING R R 5 Bov�nanville, Ontario L 1 C 3K6 10 Septic Tile Bed Systems TMENT Proposed Subdivision �� Part of Lot 9, Concession 7 Town of Newcastle Dear Sir: This letter is in response to your letter dated February 14 , 1980, in which you requested my opinion on certain aspects of septic tile leaching beds design. Your first question deals with lot sizes in relation to soil conditions . For your information, I have quoted below, Section 9 of the Ontario Regulation 229174 made under The Lnviromental Protection Act, 1971 . 9. "No person shall locate or cause or permit the location of a leaching bed , (a) in an area which has an average slope which exceeds one unit of length vertically to four units of length horizontally; (b) in soil which has a percolation time greater than sixty minutes or less than one minute; (c) in an area other than one having a depth of at least five feet of consolodated soil at every point in the leaching bed; and (d) so that a distribution pipe installed therein or any part thereof is closer to the items set out in Column 1 of 'table 4 than the horizontal distance set Opposite thereto in Column 2. " s 2 . ?a Table 4 f Column 1 Column 2 Dwg Well 100 feet Drilled we'll with watertight casing to a depth of 25 feet 50 feet Building or structure where the bottom of the distribution pipe is below the level of the lowest floor, in the building or structure 10 feet Building or• s;trur,ture where the bottom of the distribution pipe is on the same level or above the level of the lowest floor in the building or structure 25 feet Property boundary 10 feet Lake, river, pond, spring , stream, reservoir 50 feet These requirements are illustrated in the attached Drawing. 1 , which was taken from the Ontario Ministry Septic Tank Systems" published by, Information Services Branch, 135 St, Clair Avenue, West, Toronto, Ontario, M4V 1P5 . It should be observed, that the regulations do not specify a minimum lot size for trench type septic tile leaching beds , according to the soil~condi- tions . Instead, the Act gives four requirements , all of which must be satisfied. Three of the four, requirements are fixed, and are independent of the soils . Item (b) limits the construction of normal trench type leaching beds to soils which have j percolation Lime between one and sixty minutes , for, a {.percolation time between these limits , the total tile lengths and hence the actual size of the bed are determined. The minimum lot size which can accommodate a given bed area depends on the geometry of the lot, since the other requirements must be satisfied. As a rule of thum_ ba minimum lot area of 15000 square feet is normally assumed. On this basis , it is my opinion that the '-z to 3/4 acre lot sizes you propose for the subdivision should be satisfactory. If the percolation time exceeds sixty minutes , a raised bed, comprising of suitable material , must be used (Dwg 2) . u 153 - \ �.� l (� I Your second question deals with the acceptability of well log reports . Well loci reports are prepared by drillers , whose objectives and qualifications are quite different from that of a geotechnical engineer. The records have been used widely as a guide to the soils in an area , but are by no means accurate or reliable. Consequently, conclusions based on such data could be erroneous , and misleading. Finally, the successful performance of a leaching bed depends on the in-situ penneabiliiy of the soil . To this end , Section 22 of the Act, requires that percolation Lests be undertaken at the location of the leaching bed. Your observation that other houses in the area have had no problems with their leaching beds , is a good indication that the soil conditions are likely to be favourable for normal trench leaching beds: However, the Act requires percolation tests to be performed at the location of the tile beds . Consequently, at this early stage of planning , it is recommended that representative percolation tests should be undertaken at the site. Such testing would have to be carried out in late spring , when the ground has thawed. We trust, that the information contained in this letter is satisfactory for your purposes . If you should have any questions , please do not hesitate to contact this office . Yours very truly, THE TROW GROUP LIMITED D.E . Thompson, P. Eng . Branch Manager Eric . DET/sp MAX -allcl-ll-46'so-1110, llr.--_.-50'GRAVfTY ;:ED-100'2,03ED BED- ------- - -- L-E ZC H-N-G-3 P-0- (DR "N TIE P--01:E C TE 11 SEC D-,ELLI'JG (TRENCHES 61tw,4 ;CENTRES i 50'%l;tl CJST- CE TO z 12 LCLE AR-�,N-E u L L-5 0'"A I N L L ED WELL L C SE D PROPERTY LINE -LOW GRQuNo P"ECHBOURS WELL--^j TYPICAL APr;,'- L'.1EN F :)F IN SE;TIC S, The above lavout is for a •ach—g bed methods. 2. Location of tank bed to he on I •ro. "J or sr)rinqs, if pos,,t!, 3 Internal o(j-nbin--- an,7 -,2 n dratn,- rje )Ut,,, Shot,' • b•' to c,rint-cting to POSSIO!" 'utulc san,!.iry srw(,rs 4. Rout water, surface diacharg,! from fr)ot.--, etc 7-j t I exclud�:d from entr,✓ t•, >tCitic tank 5. Leaching beds NOT to '.0cated in Swamp-, grcj,,n or in j,jlj, J, Flooding. septic tank systems geneml layou' Drawing 1 N.07 T C 7, B .TC"•3OF Ft:LS'. I MOTES � jJJJ 1—SEPTIC � � I C�;LE ,1 TANt. ..�. i ^1aTl .... t I 1 DYWELIING I I �I 5�� I I �-"`...� FILL i I I DIRECTION OF POSSIBLE # I I I I EFFLUENT TRICKLE//' , SLOP:7 --STEEPER I GRASS = = r PATIO ADDEC�T NATURAL I — xtL .I I POUtROUS I 3`r t rr OF NATURAL POUROU$ SOIL OR - SOIL tC TE FILL BETWEEN SOIL Orf; C ROCK I.IPERti3O,LS PRO,"ICE ROCK I SCIL OR I,oGH WATER TABLE 6 BCTT At OUTCROP ABSORPTION TRENCH O Or PapFiLE,r SECTION A-A I PLA% AND PROFILE T�'Pt,' ,L KaI�Et F,LD ES I CIrJr3ncci from buildings, wt 11ne,. __I,. etC J, !Jr rurmJl leaching bee,-Svc a and drawing Nc G I ;, _ each 1 fUOt pert:cal that ,urtace of bid I, ,lt),)%c �L F,II ,lope must be 5table for tt3c rnJ(rr- ,yi _,eJ. but nu! ,teeper than 2 feet hur,;onL.il to I foot vertical P,�rcolarlon rate "t" to suite irnp�:rtczl n:.a. r-,.l� t?ut ,�,�[ Ie,S th3r. 5 r art, select I�n)Ih of J n fn DSurptton trenc !r„ 7,.L,,- E;tli,ent pJsimy through f i l l rn.si L e .It.,.v 1:r�: ant , na turJ1 ,.iii L.Cn_th the htl or Into the 5urruunjing perr..,,u Ie y,I, :.r,hout Ii.m.71r�I or 1,ritJl-_oL,t W ,urf.3ce Where the naturJ! Soll C".r- I, �r.e,1.•,lL.Jte ror th,, pt,rpun,! for a .IIStJr)ce of ;G feet from the uaJ in Jr.. J,�,.ct�:�r, ,t3 „hlch ,•trl,nt •:,,II [,:.,.i. ,.•I,.IL,JtI sill mu,[ L)Q .jt;,orpt„in tren,h ..,n,tr:,. ;.. .. , ,.., , se ptic tan— raised leaching bed i typical layout I NOT S._gLC i1g 5 � I Drawing 2 29 - (� ) 89CadingvimwD/ive v ' Raxdale(7onzn|o). Ontario k49WSE4 Telephone(41G) G7S-8484 February 26, 1980 File #I909-003 E� V Mr. Bernhard W. HSmiUg` MAP 3 loon R.R. #5, DUNmaDVillC, Ontario, LIC 3K8 Dear Mr, HEmhnS` Re :__ Tyrone Your letter of Feb. 14, 1980 ID addition t0 the text on pages 52 & 53 Of our report as referenced by you, you should also be aware of the C0DteDt5 of Appendix B of Our report which i3 a brief outline Of the methodology followed in completing this assignment. l\ Silty clay soils are quite predominant in the southern areas of Durham. Because our work was limited t0 8 review of available information and did Dot include site soil testing it COO be expected that some variation may exist, other than as identified by US . Our drawing No. 15 indicates that throughout « the soils are silty clay with some areas Of steep slopes and high water tahle, l would doubt that extensive areas with highly permeable soils would 8X1St in Tyrone. 2\ Tile field baCkup can only be caused by the inability of the water to 8xf1ltr3te from the pipes into the surrounding S0� lS . Due to the presence Of low permeability soils we suspect that failure occurred because there is insufficient length of tiles Or the field i5 located in 8 high water table area. Plugging Of the pipe due t0 sludge overflow from the septic tank would cause the same problem. 3) A site so s.. nvestigation should be carried out to confirm the actual percolation rate and lot sizes adJusted accordingly. In a few instances it may be found that 1.5-acre lots would be too small . However, we would expect that in general the lots could be smaller. . "` last "="^o.cc from Appendix o states "development of the community on the basis outlined, should not in the future result in unsatisfactory conditions , which would require the installation of communal services. " ConsuUingEngiooei dP|annom ' ` V Mr. Bernhard W. Heming , February 26, 1980, Page 2. 4) Our findings were that some wells are quite adequate while others experience water shortage during the summer. Generally, there are no serious problems now. However, if the community were. to develop to say a Population of 300 then we would anticipate significant difficulties as the new wells could reduce the capacity of present wells. Test drilling would be required to confirm the aquifer capability. 5) The words "major" and "larger" are relative to the size of the existing community. In the case of Tyrone a population of 300 would be considered as major when comparing to the Dresent Population of 150 people. G) Our company could conduct additional tests in the area to confirm the suitability of the soils for septic tank and tile field systems and the ground water capability. This work would be carried out using a soil testing company and a well drilling, company. I trust this information adequately responds to your inquiry, but should you wish to have further clarification please do not hesitate to contact me. Yours very truly, UNDERWOOD McLELLAN LTD. Karl Reichert, P. Eng. , Director, Environmental Engineering & Assistant Branch Manager. KR/wf S1__FE INVESTIGATION SERVICES LIMITED 677 CROWN DRIVE RETERBOROUGH, ON-r. K9J 3W2 RHONE (705) 743-3850 March 5, 1980 MAR 6 11080 - S [PLANNING p Lr p p J� ..7 TF IT MR. B. HEM ING OV4 TMW 0": tir'- R.R. #5 Ls BOWMANVILLE, Ontario LIC 3K6 Re: Proposed Subdivision, Part of Lot 9, Conc. 7; Town of Newcastle (Formerly Township of Darlington) , Ty.rone. Dear Sir: We have reviewed soils and water supply data relative to the proposed subdivision. Our comments are as follows: TILE BEDS Near surface Subsoils consist primarily of stony sandy silt till that contains some clay. However, there are some sand and clayey silt lenses in the till and there also is a discontinuous covering of silty sand and clayey silt. Groundwater levels generally are more than 15 feet below ground level but water may temporarily accumulate in the upper silty sand pockets during wet periods. There appears to be a small seasonal spring in the low area near the north-east part of the site. Surface drainage is very good. Specific soil data will be required for detailed design of tile beds . However, conditions are such that we see no problems using conventional tile beds at this site. 'rile bed areas should be levelled by adding sand fill , rather than by -cutting,, to take advantage of the lateral dispersal provided by pockets Of silty sand. For preliminary design purposes it would be reasonable to assume a design percolation rate of 30 minutes per inch (requires less than 3000 square .,fNVESTIGATION ERVICES LIMITED feet of tile bed surIrace area for a 3 bedroom home). New tile beds will not have any effect on existing development in the area. One half acre lets would provide adequate area for a house, well , tile bed and a replacement tile bed area. We see no reason for having larger lots than this for the bed purposes. WATER SUPPLY There are several shallow dug wells in the hamlet but most are drilled wells from 60 to 210 feet deep. The drilled wells obtain water from extensive sand and gravel seams in and below glacial till soils. These sand and gravel zones are excellent aquifers yielding 5 to 12 gallons per minute peak flow rate in most cases using standard well installation techniques. We consider the water supply aquifers to be capable of supporting development far in excess of the two presently proposed small subdivisions. Some of the shallow dug wells are marginal in that the depth of well below the groundwater table is small . These wells may go dry during seasonally dry periods but the added wells in the Tyrone area will not have a major influence on this occurence. In actual fact water obtained from the deeper aquifer may even help maintain groundwater in the shallow depth range. Should you have any queries concerning the information provided, please do not hesitate to contact me. Yours very truly, R. Marttila , P. Eng. RM/1p SITE INVESTIGATION SERVICES LIMITED 2 C'e,