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Clinton News-Record, 1983-04-20, Page 46Valleys dnd People Page 7 Creek Conservation ould like to send your on the development tit the Area please write ur phone the Conservation Authority s office. I3ox 5 lhroxeter 335 3557 opment objectives for Naftel's Conservation Area . y to develop troth and plantation pian programs tor the site to improve er production Ile habitat S. to develop a stream lent program through ank erosion control 1 i t oNI1,11 \I•I'% RI•.1. 1IIl)\n to develop an out door Inter pretatiun program RI'Rh::1•I'Il)1 . toruv ide ex tensive toms of day use rec reation through the develop tient ot cross country skiing and hiking trail systems pit ltll•1 • • 'w1 • _Muir A�r�r y���y�.i�. yi \'•. flim';' AA 444" . 61 1011Z44-' b y In September of 1982, the Ontario goverwnent an pounced the planning policies which municipalities and conservation authorities are to follow for regulating land use in floodplain areas These policies are to be used as a planning gwde by local governments to ensure that future housing and other developments will not be subject to an unaccept able level of flood risk The objectives of these provincial policies are to prevent flood related loss of life, minimize property damage and social disruption and to encourage a coordinated approach to land use and water manage inent The Province has delegated the responsibility of im- plementing these policies to the local municipalities and the conservation authorities. To meet this responsibility, the Maitland Valley Conservation Authority has established a compre- hensive floodplain management program The purpose of this program is to assist municipalities in identifying floodprone lands and to implement measures to reduce the effects of flooding where development is affected. This assistance takes the form of providing flood warnings to municipalities, providing funds for capital projects such as channel improvements and the acquisition of floodprone developments. In this article we would like to take time to outline in more detail the criteria and policies which have been set out by the Provincial government. FLOODPLAIN DEFINED First let us examine what qualifies as a floodplain. A floodplain is the relatively flat area of land beside a river or stream. It is an area naturally prone to flood- ing. This land is actually part of a river's living space, which it uses from time to time to carry extra water that enters its system. Because of the area's suscepti- bility to flooding, buildings constructed within its boundaries are most liable to water and -or ice damage. FLOODPLAIN BOUNDARIES Because ekery flood is different, the Province has set out artificial standards for calculating the limits of the floodplain. In the Maitland watershed this standard is based on the flooding which would occur as a result of a "• Regional Storm." The "Regional Storm" is based upon the conditions which occurred when Hurricane Hazel caused a devastating flood in the Humber River Valley in Toronto in 1954. These conditions are trans- posed over the Maitland watershed to determine the limits of the floodplain. While this standard is fairly high, the Province allowed some flexibility in its policy options for municipalities and conservation authorities to use in planning floodplain lands. This flexibility allows for the Authority and the municipality to identify another flood line based on a lesser flood event in areas where there is extensive development already in the floodplain. This lesser 'The Maitland Valley Con- serva tion Authority is work- ing with each municipality ... to deal with their floodplain m an ager en t pro_bl eros. " flood event is called • 1 loo year' floodline The WO year flood is based upon an analysis of past flooding records to determine the magnitude of a flood which would have a 1 percent chance of occurring in any given year FLOODPLAIN MANAGEMENT ALTERNATIVES In areas where there is extensive development a floodplain management policy may be developed which incorporates both the 100 year flood (minimum condition) and the Regional Storm, (maximum condi, tion) The diagram below illustrates the flood boundar- ies in a typical floodplain. That portion of the floodplain falling within the 100 year flood criteria is referred to as the FLOODWAY The area inside this boundary belongs to the river. It has flooded frequently in the past and will flood again in the future The Maitland Valley Conservation Authority, through its floodplain management program is working with urban munici palities to develop a suitable policy for dealing with development in the floodplain. The area between the 1 100 year floodline and the Regional Storm floodline may be considered for development provided that this development is flood - proofed. This portion of the floodplain is known as the FLOOD FRINGE. This area is outside the FLOOD - WAY and extends to the Regional Storm flood limits. This type of floodplain management policy, in- corporating a FLOODWAY and a FLOOD FRINGE, is referred to as a 2 -ZONE approach. While restricting development within a portion of the floodplain — the FLOODWAY, this approach allows limited develop- ment to occur in other portions of the floodplain which are not as susceptible to flooding on a regular basis — the FLOOD FRINGE. The feasibility of implementing the 2 -ZONE ap- proach is dependent on the physical conditions of the site and existing and proposed land use. Before such an approach is implemented, consideration must be given to the effects any development will have on reducing the flood storage area on flood levels and consequently increasing the risk of life and property. SPECIAL POLICY" AREA APPROACH The historic development of towns and villages, near rivers in the Maitland watershed illustrates the dependence of industries on our river systems In some towns, extensive development within the floodplain means that the application of a 2 -ZONE approach is not possible The towns of Lucknow, Harriston and Listowel are excellent examples In these situations the central portion of the business section is located directly atop the river channel The river passes under streets and stores by means of a cement channel or 'conduit' Flood flows are typically too deep or too strong for the channel to fully protect buildings from flood damage In these exceptional circumstances, a SPECIAL POLICY AREA may be considered This approach is only taken in urban municipalities where the maintenance of development in the floodway ►s deemed necessary to the economic well-being of the town or village, and, the risks from flooding are ac- ceptable to the municipality, the conservation authority and Provincial government. This approach can only take place with the approval of the Province of Ontario and the Conservation Authority Before approval may be given to the use of a SPECIAL POLICY AREA, the municipality must prepare suit- able documentation to demonstrate to the province the necessity of being granted special consideration to allow existing development to remain in the floodway. FLEXIBILITY THE KEY From our description of the Province's floodplain policies one can see that there is some flexibility to develop a policy which meets the needs of each munici- pality. The Maitland Valley Conservation Authority is working with each municipality, as we are contacted, to deal with their floodplain management problems. The Province's concern over growing flood damages and the local municipality's concern to protect the economic well-being of its residents are given equal consideration in the Authority's approach to floodplain management. For more information on the Province's floodplain policies and -or the Maitland Valley Conservation Authority's floodplain management programs, please contact the Authority office in Wroxeter. THE RURAL SITUATION Because of the geographical size and the fact that residents are few and further apart in rural munici- palities, the severity of flooding in these areas, is often underestimated. At the same time, it would be fin- ancially impractical, if not impossible for rural municipalities to undertake elaborate floodplain management projects and flood control measures to reduce the effects of flooding for a small number of developments. Where the river valley is deep, flooding does not pose Continued on page 8 725 72S P 48.85 ha Typical Cross Section of a River Valley FLOODPLAIN L ANDS p0 LIJ FLOOD FRINGE �111'l1 's1I rhl,I Wig z XiLLI FLOODWAY 0 CCA1F 6 A • n u. 2n 1.CC CHECK BEFORE YOU DIG—If you are planning to construct or renovate a building; place fill on property near a watercourse; or alter a watercourse you should first contact the Maitland Valley Conservation Authority to see what the potential for flooding is, and if there are any regulations you are required to abide by. REMEMBER: floodplain regulations are for your pro- tection and will ensure that your investment will be better pro- tected in the event of a flood. NORMAL WATER LEVEL