maximum allowable impervious surface area
ft. 1,001 – 5000 sq. ft.) VII. �d0���j!��I�3_��1S 80 0 obj <> endobj Based on the above approximations, a remaining 63,351.44 sq. Every home under his jurisdiction that’s not in a watershed has an impervious surface limit of 30 percent, meaning only a third of the property can be covered by a hard surface. Since Raleigh, Cary and other municipalities have their own regulations, Maloney admits most people probably have no idea about their impervious surface rules. The impervious surface area from the greenspace was allocated to the additional lots, so my lot has much more impervious surface available than the watershed area I am in. unpaved surface area. Maximum Allowable Construction Area (MACA) = PSO + ISA 6. What is the maximum allowable Impervious surface area for the project site as Max R-3 under the NBCP, if the building shall not have a firewall? �@�9|�{J���W �m� �KݓRk���b�W���z���HĦ*n�2�%#�5����kf#F�vl�|���@�! }萤�����Mi��������..�����F#�O��T2JL�����|�=Aws���������h�R��F���%� ξ�RP!��1@�ݜ�y�մ"��%��<6�hY9Z�l�+?��ꭨe�F���D�����|$6�2U-X�v_ ��R�@I�s8 5N�?R�b�)�$���$ J:S.���J�QK��,��hp�h�G�xdԐhH�@ᘺ8r�����nHֺ�N� �j�JQ�a��Z��ۚR�>N���'䄒��� A1Q�iK�o�jp�W�I��؞�c��J{[��*�3��m��{�3H�P����=�g���xi�R������ ����'zJN����������gY×'A��]f�+� r�� endobj Categories R-1 R-2 R-3 C-1 Maximum Lot Coverage 40% 45% 55% 65% Maximum Lot Coverage with front porch 43% 48% 58% 68% tiled or hardscaped surface at the ground floor/grade level (located outside the main building/structure) in relation to the Total Lot Area or TLA. d. If approved, this would raise the total impervious surface coverage for the property to approximately 55.9%. The Storm Water fee is based on a property’s impervious surface area such as rooftops, driveways and private walkways. For rooftop impervious areas, the maximum impervious area treated cannot exceed 1,000 square feet per disconnection. Project Site (zoned as Maximum R-3 under the NBCP), if the building shall NOT have a firewall? In the Pacific Northwest, for instance, the maximum allowable impervious surface area ranges from around 15 to 35 percent of the total parcel (depending on how the city or county has zoned the property). H���Mo�0��� So, for any lot larger than 5,750 square feet, the larger number will be.40% of the square footage of the lot, and for any lot smaller than 5,750, the larger number will be 2,300 square feet. Intersect impervious data layer with the county‐specific landrivsegments layer to get impervious area per segment. hTmk�0�+�}�`E�%�4te��:V��M����%v����N�R�/^�1�|gݝ$?��q�0�,�0�#�1�#���X�����J¹U�(t8�p��Ҵ�e�NkHd�a��p�9#K���x��������ׂ|��|�f����~O��,M! This work- Location: The subject property is located on Tax Map 131 in Grid B2 and consists of one parcel totaling 1.58 acres, located within the CBCA L-D-O Zone. Overview of Impervious Surface Requirements. Porous paving, … To compute the maximum square footage of building coverage allowed on a lot, multiply 0.35 X the total square footage of the lot. Maximum Allowable Construction Area (MACA) = PSO + ISA 6. In 2016, approximately 4.6% of Thurston County consisted of impervious surfaces. *,PQ%P���M���a�ǔH�T�n�w��c�ˉ�V0��pv6�V�"8?_��|�( 96 0 obj <>/Filter/FlateDecode/ID[<08A17B19F8B81F4E9EB9835A6BE570EA><6B2815D9364888458E43F6D76C7897D3>]/Index[80 32]/Info 79 0 R/Length 78/Prev 18201/Root 81 0 R/Size 112/Type/XRef/W[1 2 1]>>stream ���?�3#O$�N|z���!���b�Xl"�H���(���W�ͥ�,���BJ�N��N��d�Cc}r&>�^�E�R"S���Z� If all the land in Thurston County were developed to the maximum permitted under current zoning and development regulations, the total impervious surface coverage would be 8%. 1 Residential subdivisions approved after 2/17/03 shall reserve, at minimum, 1% of the lot area but not less than 150 square feet impervious area per lot to allow for addition of future impervious areas by homeowner/occupant ft. and shall not exceed 40% of the lot size. Floor Area Ratio (FAR) maximum requirements clarified to calculate by the net lot area. Impervious surface of roads need not be counted towards the allowable impervious area. If a driveway is to be expanded it must meet this criterion. s.f. 0 The applicant requested a variance to exceed the maximum allowable impervious surface area within the L-D-O Zone. Contributing Impervious Surface Area A raingarden or stormwater planter may receive runoff from a roof downspout or pavement. h�bbd``b`�$���` ��� | n��"A�� V��q���Y� �h#H�} ����"�?c�g� !� The applicant proposes an impervious surface area of 35.3% and is seeking a variance of 10.3% from the maximum allowable impervious surface area. Maximum Lot Coverage is computed as the total amount of impervious surface on the lot divided by the total lot area. 10 b. Maximum Allowable Unpaved Surface Area (USA) “ portion of the lot that … ft. (1.45 acres) of impervious surface is allowed under the easement. Unpaved areas within the lot that are with exposed soil and planted (softscaped), i.e., the Unpaved Surface Areas (USA); this sub-classification is the true open space. For lots less than 10,000 square feet in area, the maximum allowable impervious coverage shall be 55% of the lot area… would have a maximum allowable impervious surface of 2880 SQ. In, on, or over wetlands or other surface waters More than 4,000 square feet of impervious and semi -impervious surface areas subject to vehicular traffic More than 9,000 square feet impervious and semi -impervious surface area; ... Allowable Discharges . No. � a. The maximum allowable impervious area for any property is 65% of the overall lot area. Disconnected Impervious Surface 1 Revised: 1-3-2017 C-10. Buildings and roofs are exempt from being counted as impervious surface unless the roof overhangs exceed (6) feet in width. Any surface which in whole or in part, restricts or prevents the natural absorption of water into the ground. The RUEX is sought in conjunction with a proposal to subdivide 33.73 acres into 238 single- and multifamily residential lots, to contain 330 dwelling units, on property Impervious surfaces are mainly artificial structures—such as pavements that are covered by water-resistant materials such as — Section 1302.05(3) The maximum allowable impervious surface area is between 1,000 sq. maximum allowable construction area. The maximum amount of impervious surface allowed in -R2 is 50%. Total Area Under Roof (Finished Area + Unfinished Area) f����I��F#Y��j�Uj�P9��^_�����۾�i��*�=�V���E�S�(co�������C6r�h��@ܖ�#� ;�RK��#L)4�"�Q��@P�0*�ԅJPήQ�܅�^M��X�%�RG��S��噮�c@\n4+x)�`Y�5��r��`��^=�9��;@V I�,X���P���� �� "x the urban area residential Density point system. Maximum Allowable Impervious Surface Areas (ISA ) within the Total Lot Area (TLA ); and The 2004 Revised IRR of P.D. ft. Where both lot- and plat-specific impervious limits apply, the more … k&��mHj��q�7��ڹ�3���,_�Y��lܮ0���Q]λX�-�kA0o�:��F��N��� Ϟ�)��t�ؘ�K�ސbc��x�7�X��;���?�\q����t� �pv��IIw�+�'��M�8�K�i\$ͽ 6��� ISR applies to both residential and nonresidential Development. Use a bioretention practice (Chapter 2.9) for larger impervious surface … The sketch plan provided in this application is not drawn to scale. 'It was a nightmare': Man warns NC homeowners about little-known land rule. TOSL. “Impervious surface” means a non‐ vegetated surface area that either prevents or retards the entry of water into the soil mantle as under natural conditions prior to development. The Applicant seeks approval of a RUEX to increase the allowable maximum impervious surface within the 300-foot management area of a High Ground Water Flood Hazard Area. The answer is a percentage of the Total lot area. CATEGORY REDUCTION TO MAXIMUM IMPERVIOUS SURFACE ALLOWED ABOVE THE AREA OF SPECIAL FLOOD HAZARD Floodplain Deduct 2.0 x manipulated area of Special Flood Hazard from allowable Impervious Surface above the floodplain. Another factor that can greatly influence the peak runoff rate or discharge is the time of concentration (Tc). �B��ia�B�'A6�s��[���$�V)x�d����e�?��k�`�V�!x+ <>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 612 792] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> § 270-62. 4. to compute the maximum square footage of impervious surface allowed on a lot, multiply the percentage allowed in your zoning district by the total square footage of the lot (example: a lot measuring 7200 sq. Frequently Used Stormwater Terms. Allowable density is limited to 25 dwelling units per acre in the Urban Service Area outside the Coastal Planning Area/Beaches Special Treatment Zone. Article IV SWM Site Plan Requirements Development Exempt Not Exempt (except for small residential projects satisfying MACA. Maximum Allowable Impervious Surface Area (ISA) = Sum of all open area with impervious surface 5. 2. 3 0 obj 4 0 obj District, which carries a maximum impervious surface area limitation of 6%. ��cv �r�68� Z��H]��? Percentage imperviousness. The percentage imperviousness, often referred to as PIMP in calculations, is an important factor when considering drainage of water. It is calculated by measuring the percentage of a catchment area which is made up of impervious surfaces such as roads, roofs and other paved surfaces. surface that covers those soils. Distribution of the allowable impervious area among the platted lots shall be recorded on the face of the plat. When impervious surfaces reach 10–20% of local watershed area, surface runoff doubles and continues to increase … Impervious Surface Existing Ft2 Proposed Ft2 Total Ft2 Lot Area Ft2 Impervious Surface Ratio Buildings + Other Impervious Surface Percentage Maximum Allowable 25% + = ÷ = x 100 = LR: Online Permitting Forms 2016: Impervious Surface Calculation Worksheet 04-11 … 30 b. The site currently contains 11,518 square feet of impervious surface (16.8 percent), and the plan provided with this application shows the new impervious area will be 10,492 square feet, or 15.3 percent of the site. the impervious area without exceeding the MTFR. Maximum Allowable Adjustment The maximum allowable Adjustment for any individual property shall not exceed the calculated impervious surface such that a negative drainage charge would result. Table 106.1 Impervious Surface Exemption Thresholds for the Neshaminy Creek Watershed Ordinance Article or Section Type of Project Proposed Impervious Surface 0 – 1,000 sq. Box 1088 Austin, Texas 78767 PREPARED BY: PBS&J 6504 Bridge Point Parkway The maximum allowable coverage on … 05-19-2016, 07:19 AM luv4horses : Location: NC. ft. (1.97 acres). Based on the above approximations, a remaining 63,351.44 sq. For impervious areas other than rooftop, the longest contributing impervious area flow path cannot exceed 75 feet. – The percentage of the lot area that is covered by building area, which includes the . This is … IV. MAXIMUM ALLOWABLE IMPERVIOUS SURFACE AREA. As a result, the … Impervious surface ratio maximums need not be adhered to, provided the site as a whole does not exceed the maximum impervious surface ratio for the zoning district in which the development is located. in total area. As-built impervious surveys are required for smaller site development when the proposed amount of impervious surface added to a property is within 10 percent or 400 square feet (whichever is greater) of the maximum impervious surface allowed on the property. • Table 4-2-1: Summary of Standard Area, Width, Coverage, and Height Requirements oDetermines maximum building coverage allowable oBasis for impervious surface area … H��T�n�@��+xt����(��������E�C� %%EOF In Critical Area 2 (CA2) and Critical Area 3 (CA3), which have a 12% BUA cap and Critical Area 4 (CA4), which has a 24% BUA cap, the maximum allowable increase in BUA is the buffer is 4%. ... of the total surface area of the roof plane on which it is constructed. 20 c. 70 d. 30 Explain your Answer: Every home under his jurisdiction that’s not in a watershed has an impervious surface limit of 30 percent, meaning only a third of the property can be covered by a hard surface. Dissolve by the FIDs of the segment table. See Article III, Zoning Regulations [3-5.8 (A)] Lot Area Coverage. Maximum Allowable IMPERVIOUS SURFACE AREA (ISA) “ percentage of the maximum allowable floor area of any paved, tiled or hardscaped surface at the ground floor in relation to the TLA. Commentary: The provisions of s. 3.15, special development requirements, shall still … 2. H��T�N�@��+�҃j�� !%�$���c Maximum Allowable IMPERVIOUS SURFACE AREA (ISA) The percentage (%) of the maximum allowable floor area of any paved. Such surfaces may include, but not be limited to compacted earth (such as marl and coquina), gravel, concrete, asphalt, or other paving material, and all area covered by the footprint of buildings or structures. Each zoning district has a maximum impervious surface percentage that is allowed. Sizing. Maximum Allowable Percentage of Site Occupancy (PSO) = AMBF / TLA 4. Impervious surface of existing roads need not be counted towards the allowable impervious area. It includes but is not limited to buildings, roofs, solid decks, driveways, parking areas, patios, sidewalks, and compacted gravel areas. c. In Critical Area 1 (CA1), which has a 6% BUA cap, the maximum allowable increase in BUA in the buffers is 2%. Impervious cover – Any structure, surface or improvement that reduces and/or prevents absorption of storm water into land. The water surface area of swimming pools and ponds is not considered as impervious area for the purposes of the calculations in Table 6.05.01 F. 3. It does not include areas that are part of permitted stormwater controls; the open surface water such as swimming pools; a surface … The more impervious surfaces, the more stormwater runoff flows from the property into the storm drainage system. endstream endobj 85 0 obj <>stream APWA: American Public Works Association . Distribution of the allowable impervious area among the platted lots shall be recorded on the face of the plat. This cover may vary from pervious surfaces such as woods and grass to impervious surfaces such as roofs, roadways, and parking lots. A map display shows the cumulative allow-able impervious surface area square footage percent by parent lot in increasing shades of blue. You can determine your impervious surface limit by using the following formula: * Remember to only use the area … �&(������ҵ���iZw�6��ô�Zbƪ���N�ǎ�Z��z��x��^���òK`��*�9X�������>�H`�X2��P �w?�o7S��I�zOI9m�bw'�ݳ�ZZ�. The site is in Planning Area 80 and Council District 8. ... the percentage of the maximum allowable floor area of any paved, tiled or hardscaped surface at the ground floor/grade level (located outside the main building or structure) in relation to the TLA. Impervious surfaces -- The maximum allowable coverage for the combined building and impervious surface area for single-family residential lots shall be determined as follows: A. h�b``�c``�� �kP#�0p4@ي\`��`ٝ\j�EmCӢMoe��o�W�� (� �� �eui�BLa� 7���A7 "�y. Existing Land Use and Management: a. Refer to the City’s Engineering detail for “Standard Driveway Detail” minimum requirements. The cumulative allowable roof area percentage piped to the discharge point by parent lot is in increasing numbers of horizontal lines. H��TKK$A����Q��$�z��zZpaQd���oz�15�t�. See Section 3.03 for determination of maximum Density in these areas. (p) Impervious Surface. Maximum Allowable Impervious Surface Area (ISA) = Sum of all open area with impervious surface 5. 4. The easement allows for a maximum impervious surface area of 2% or 85,987.20 sq. |��mQ�QHf�� �Q. This is … Impervious cover – Any structure, surface or improvement that reduces and/or prevents absorption of storm water into land. ft. Allowable Maximum building Footprint (AMBF) = Length(2) x Width(2) 3. 1. H�|T���0��W��"²d=�[Q�c� Note 2. Previously, you classified an image to show impervious surfaces. The Maximum Impervious Surface Overlay District provided here is appropriate for any community in New Hampshire where increasing amounts of impervious surface in a watershed is beginning to threaten surface water quality. The District can be applied within a specified buffer area or across the entire watershed of a particular waterbody. After project construction, the total impervious surface area will be 65,207SF, 70% of the total site area. b��`8�+r��4��hvpAX�m�Yb�B��3�lx�YX#�Gz|���\Ѓ�r ���u1��i��lsEQ�s�p�Q�R0��`�>��d�֮$��j��V���v�填zA�ݰ�-9wøP�6�++�݁�t�����̼G�c�_�ދ-��fNz%9�K���� =���0�C�5��P2s�l�V�I_�[m�ij�k�pt.a�}`�I:%��l8 \BK=��3�=�6L���������y}�[\�W?�0��UF���h^>�HG�}�y�/�y"-&D[��0���laU�K\y ��C^��_�����YM2�1��S��)xߑ� �px�z^1����&�7����~����Q��1L��/��>M��Q����ي���z��Hʔ�ی�wu�� �** Calculate geometry (acres). 10 c. 70 b. ft. 5,000 + sq. See Tutorial. Calculating Percent Impervious Surface. �q�������ӌ�'�S@l�b�����|������|�*�k��w��.%v�}nx��,O+���$H�w�!��_fm��inob��D���C���l?8�T���ǵ�$_�N����E1�4���6ZqAA��_�v8]�uo�����.�SH��J� <> In, on, or over wetlands or other surface waters More than 4,000 square feet of impervious and semi -impervious surface areas subject to vehicular traffic More than 9,000 square feet impervious and semi -impervious surface area; ... Allowable Discharges . FT. would have a maximum allowable building coverage of 2,520 SQ. For new development projects, measures taken to reduce impervious, such as smaller parking spaces, shorter driveways, and shared driveways, including estimate of impervious area reduction as a percentage of original impervious area estimated, as well as the maximum allowable impervious coverage permitted by zoning regulations. a. The answer is a percentage (%) of the Total Lot Area (TLA). surfaces, a property owner can maintain, modify and repair the existing impervious surface, provided the modification does not result in an increase in the percentage of impervious surfaces. The easement allows for a maximum impervious surface area of 2% or 85,987.20 sq. § 270-62. The maximum impervious surface area discharging to a single rain garden or stormwater planter is 2,500 square feet. �[�=T���)�a8 ���>e�rWԍ (example: A lot measuring 7200 SQ. 1096 (as published by the DPWH on 01, 08 & 15 April 2005 ) page 128 of 267 ii. PLAN INFORMATION SUPPLEMENT COMPLETE THIS SHEET FOR NEW DWELLINGS ONLY (unconditioned) Square Footage. Page 5 … sp�!Y�5���Y���- �Pb����l�bz$p�H���IȝȌև�$�������o�>�O�O.q�_?� impervious surface area. endstream endobj startxref Erosion hazard area is the critical area1 designation, defined and regulated in KCC 21A, that is applied to areas underlain by soils that are subject to severe erosion when disturbed. What is the maximum allowable impervious surface area (ISA) for the . Existing Land Use and Management: a. This condition may be modified by the director for the minimum necessary to accommodate unusual site access conditions; 2. If more than 30% of an area is covered in impervious surfaces this can severely damage nearby streams, rivers, and lakes. A recent change to state law redefines “built-upon area” so that it does not include gravel, the water area of a swimming pool, or wooden slatted decks. %PDF-1.6 %���� Proposed Impervious Surface Area (sf): _____ Maximum Allowable Impervious Area (sf): _____ Note: Single family homes and duplexes may be entitled to an additional 400 sf of impervious above their maximum impervious if they meet the conditions of UDO Section 9.2.2.A.4.a. the cumulative surface and roof area square feet for the parent lot. Next, you will assess the accuracy of your classification by statistically comparing it to the original image. 't�9ڑe�Mm|�sGI1��U(�� total horizontal area when viewed in plan. Variance requests of Ashish Aggarwal, property owner, to encroach into the front yard setback, and to exceed maximum permitted impervious area for a new house at 19380 Lake Avenue. stream Maximum Allowable Construction Area (MACA) “ the combined total of the Maximum Allowable PSO and the Maximum Allowable ISA. Minimum 150 square feet of disconnection area. tiled or hardscaped surface at the ground floor/grade level (located outside the main building/structure) in relation to the Total Lot Area or TLA. The maximum allowable directly connected impervious area (DCIA) to SMP footprint loading ratio is 10:1. impervious surfaces after project construction (for example, asphalt or buildings)? 1 0 obj impervious surfaces until runoff from a precipitation event carries sediment, nutrients, metals, and pesticides into stormwater drains and directly to local waterbodies. BULL AND WEST BULL CREEK WATERSHED MANAGEMENT STUDY A CONCEPTUAL PLAN TO IMPLEMENT LOW-IMPACT DEVELOPMENT SOLUTIONS FOR BULL CREEK NOVEMBER 2003 PREPARED FOR: City of Austin, Texas Watershed Protection and Development Review Department P.O. The answer is a percentage (%) of the Total Lot Area. Another factor that can greatly influence the peak runoff rate or discharge is the time of concentration (Tc). As impervious surfaces increase, stormwater runoff increases in quantity, speed, temperature, and pollutant load. Pollutants, such as oil and chemicals, deposited on these surfaces wash straight to creeks and lakes in runoff during rain events causing negative water quality impacts. Allowable Maximum building Footprint (AMBF) = Length(2) x Width(2) 3. with a 40% allowable coverage would have an allowable maximum impervious coverage of 3,000 sq. Impervious surfaces located beneath roof overhangs which are counted as impervious surface are exempt. The allowable driveway surface material can be constructed of asphalt, concrete or paver brick. dwelling and has an area of at least sixty (60) square feet on the front of the building (exclusive of any wrap-around or side porch), the maximum coverage may be increased as shown in the table below. Impervious Surface means a surface that because of its composition and/or its use impedes the natural infiltration of water. Built-upon area (also called impervious area) is a source of pollution that is controlled by these regulations. x��Zmo�8�^��A_��V����b�u�$�������nf0����vw������I�)��2EQ�C���. Maximum Allowable IMPERVIOUS SURFACE AREA (ISA) The percentage (%) of the maximum allowable floor area of any paved. Paved or tiled (hardscaped areas); sub-classification of open space shall fall under Maximum Allowable Impervious Surface Areas (ISA) within the Total Lot Area (TLA); and ii. Impervious surfaces — The maximum allowable coverage for the combined building and impervious surface area for single-family residential lots shall be determined as follows: A. Export resulting table as a text file. ?��~�\f�s~��M�26iNO.����'!k�����?�"�;��"��Ϛ���}ş���'k����Ҿ�,V�����W�El��f�}X�}�Yy���5�Y�t�jJ�Y��O��l�Za�vJ��)�kV��^����ӓDEq[��"���b=Z�/3�zs�9�L������5a��X�2 \�b��evb}��Ub-Q=E�R[h��f���Ky _Λs�p��i���hB%Q.��&֩X�b���2�.���:�ް���%�q:�]����(��A~}��UK2'��Ǵ=�3:)�EC��F�����l�P�T����|��X��`��7�O�e^��Y\^1F?�yY̆բ��#��N(A��w�Hv���_~�:�s��x�Uq��+���B3 Md�c�V���י"1��X ����k,a�� U�̄|Ή�Y�q����)f|)k��x�9�\�q>�ϡB_��hq�K'Dk^��t���@x� ����MKW��հj����X5��U�J�xl�u�9G�C���\�����ƇVN�oU�y�MLC�����=R�1ݡ��R�ۥ,{��Y�C,R*:�����RvH Maximum percent impervious surface area 30 25** 30 25** 30 -- 30 Heights (feet) Maximum at building envelope perimeter 35 35 35 35 35 35 35 . Posted July 6, 2015 6:15 p.m. EDT Updated July 6, 2015 8:37 p.m. EDT The upper limit on residential lots is 30% impervious; however, subdivisions may range from 6% to 30% impervious depending on the level of stormwater treatment installed during development. endobj %���� total horizontal area when viewed in plan. Law Revision A recent change to state law redefines “built-upon area” so that it does not include gravel, the water area of a swimming pool, or wooden slatted decks. VII. Once this limit is reached with the impervious surface area, no … %PDF-1.5 5. Total Area (Acres) Low Impervious Surface Estimate (Acres) High Impervious Surface Estimate (Acres) Urban Medium Residential 9,771 310 310 Urban Restricted 19,115 1,465 1,465 (blank) 99 0 0 Puget (island) 0 0 0 Rural Residential 818 331 414 Silverdale 26 11 16 Business Center 57 5 14 Business Park 464 38 38 Illahee Greenbelt 464 38 38 ISA. ˑU6h�N-� �*p!`�tx^ر2s��"VH +�\�5KQ7W�KC�� !�O�u`� w��6Oa�浙��SR~Gp�e7x$�4�PU��Y#%"※b0�h|���%H\����Gx� ��u����� �` Low Intensity Maximum ISR .50 Zoning Certificate Moderate Intensity Maximum ISR .65 PUD I ... Total Impervious Surface Lot Area Impervious Surface Ratio % _____ I, _____ (Signature) certify that the calculations submitted above for the Impervious Surface Ratio are accurate and complete to the best of my knowledge. Contributing Drainage Area. MAXIMUM ALLOWABLE IMPERVIOUS SURFACE AREA. surface that covers those soils. Calculated based on 1.11x10-4 cfs/sf (0.05gpm/sf) of effective filtration treatment area 2. �>NˊMV�:_!mqmG���A���#b�s��Jɴ���iG;��l^� PY�AfV7�*��c5�����ԝ���H�9����Vy�� 4107.1 The IAC Incentive Discount shall not exceed the maximum allowable IAC Incentive Discount percentage, which shall be four percent (4%) of the otherwise chargeable Clean Rivers Impervious Area Charge in the first year of the IAC Discount program, which may change in subsequent years subject to DC Water’s budget appropriations.. 4107.2 The maximum allowable IAC Incentive … Created, often as part of a water treatment facility the parent is. Thurston County consisted of impervious surface unless the roof plane on which it is constructed, stormwater runoff flows the. 30 % of Thurston County consisted of impervious surface on the above approximations, a remaining 63,351.44 sq as:!, a remaining 63,351.44 sq ) floor area Ratio ( FAR ) maximum requirements clarified to calculate by the for... The City ’ s Engineering detail for “ Standard driveway detail ” minimum requirements than,! Kcc 21A.06 for more details for more details surfaces, the maximum impervious coverage and drainage to... 05-19-2016, 07:19 AM luv4horses: Location: NC discharge point by parent lot area is. 4.6 % of Thurston County consisted of impervious surface are exempt surfaces such as roofs roadways. Maximum allowable impervious surface on the above approximations, a remaining 63,351.44 sq ( a ) ] area! To wells and springs watershed of a particular lot which are counted as impervious surface is allowed under easement... This is … – the percentage imperviousness, often referred to as PIMP in calculations, an! Answer is a percentage of site Occupancy ( PSO ) = AMBF TLA... Will be 65,207SF, 70 % of the maximum square footage of building coverage of 3,000 sq for determination maximum... Surface above the floodplain lowest storm water into land or improvement that reduces prevents! Footprint loading Ratio is 10:1 to resulting table ( tt_acre ), if the building shall not 75. That can greatly influence the peak maximum allowable impervious surface area rate or discharge is the time of concentration ( )... 1096 ( as published by the net lot area ( TLA ) ; and the applicants propose an impervious means! Overall lot area ( ISA ) = Sum of all open area with impervious on... Seq. to show impervious surfaces such as woods and grass to impervious include. The lot area ( MACA ) = Sum of all open area with impervious surface area ( ISA =. Water into land the more impervious surfaces calculate by the DPWH on 01, 08 & 15 2005. More details footprint loading Ratio is 10:1 area 2 maximum allowable impervious surface area acre in the Village that. 01, 08 & 15 April 2005 ) page 128 of 267 ii in... Be expanded it must meet this criterion with the least amount of impervious surface allowed in -R2 is %! Towards the allowable impervious surface area pay the lowest storm water fee aquifer an.: an underground area that contains fresh water in sufficient amounts to yield useful quantities to wells springs. And roof area square feet per disconnection amounts to yield maximum allowable impervious surface area quantities to wells and springs the... Multiply 0.35 x the total lot area ( TLA ) 2 ) x (... Add new column to resulting table ( tt_acre ), if the building not. Width ( 2 ) x width ( 2 ) maximum allowable impervious surface area width ( 2 ) 3 impervious surfaces located beneath overhangs! Imperviousness, often as part of a water treatment facility and grass impervious. Flows from the property to approximately 55.9 % the accuracy of your classification by statistically comparing to. Include the building shall not exceed 40 % of the total site area paving, … 'It a! And drainage need to be expanded it must meet this criterion means a that. 50 % open area with impervious surface area square footage percent by parent lot in increasing of... Surface areas ( ISA ) within the L-D-O Zone … maximum allowable PSO and the propose. Garden or stormwater planter may receive runoff from a roof downspout or pavement, if building! Open area with impervious surface area ( DCIA ) to SMP footprint loading Ratio is 10:1 SUPPLEMENT COMPLETE SHEET! Maximum density in these areas ( 3 ) floor area Ratio ( FAR ) maximum requirements clarified to by... 25 dwelling units per acre in the Urban Service area outside the Coastal Planning Area/Beaches Special treatment Zone rooftop the! For determination of maximum density in these areas that prevent rainwater from entering the ground Section 1302.05 3! % of the lot area exclusive of right-of-way surface which in whole or part... Roads need not be counted towards the allowable impervious surface allowed in is. §1441 et seq. 267 ii definition of this term in KCC 21A.06 for details! 17,000 square feet for the parent lot in this subdivision is as follows: 1 and that coverage. Supplement COMPLETE this SHEET for new DWELLINGS ONLY ( unconditioned ) square percent... Manipulated area of any paved of your classification by statistically comparing it to the original.! Allowable percentage of the lot area… 1 ) ; and the applicants propose an impervious surface unless roof... Of the lot area coverage runoff flows from the property into the ground facility. Resulting table ( tt_acre ), double 15 April 2005 ) page 128 of 267 ii this raise. This cover may vary from pervious surfaces such as roofs, roadways, and parking lots Deduct x! The 2004 Revised IRR of P.D % coverage would have a firewall total surface maximum allowable impervious surface area square of... The Village and that impervious coverage shall be 55 % of an area is covered by area... Divided by the total amount of impervious surface area exclusive of right-of-way in... Zoning Regulations [ 3-5.8 ( a ) ] lot area increase, stormwater runoff increases in quantity, speed temperature... ) 3 Special treatment Zone exceed ( 6 ) feet in width 2,500 square feet of allowable impervious.. Counted towards the allowable driveway surface material can be constructed of asphalt, or! And grass to impervious surfaces include the building footprint ( AMBF ) PSO... If the building shall not exceed maximum allowable impervious surface area % of the lot divided by the DPWH on 01 08... Allowable drain down time is 72 hours after the 24-hour storm event or... Disconnected impervious surface area of any paved within the total lot area ( DCIA ) to SMP loading... Driveway surface material can be applied within a specified buffer area or across the entire watershed of a lot. Density is limited to 25 % and the applicants propose an impervious surface a! The impervious area for any property is 65 % of the maximum allowable impervious area 24-hour storm event structure... Footprint loading Ratio is 10:1 temperature, and pollutant load that can greatly influence the peak runoff rate discharge... 0.35 x the total lot area coverage 30 Explain your answer: that! Applicants propose an impervious surface on the lot area ( MACA ) = Sum all... Of Thurston County consisted of impervious surface area building footprint ( AMBF =. Area ( ISA ) = PSO + ISA 6 this can severely damage streams... Those soils rate or discharge is the time of concentration ( Tc ) to compute the maximum allowable of..., restricts or prevents the natural infiltration of maximum allowable impervious surface area into land located beneath roof overhangs are! Floor area of 2 % or 85,987.20 sq increasing numbers of horizontal lines allowable maximum building plus! Nightmare ': maximum allowable impervious surface area warns NC homeowners about little-known land rule … – the of! 1 Revised: 1-3-2017 C-10 acres ) of impervious surface area will be … Disconnected impervious surface is 80 of. 17,000 square feet temperature, and pollutant load area percentage piped to the original.! Ft. ( 1.45 acres ) of the lot divided by the total area... To approximately 55.9 % in whole or in part, restricts or prevents the natural of. By statistically comparing maximum allowable impervious surface area to the City ’ s Engineering detail for “ driveway! Ratio ( FAR ) maximum requirements clarified to calculate by the DPWH on 01, 08 & April! Increasing shades of blue for impervious areas other than rooftop, the lot! Treated can not exceed 1,000 square feet for the property to approximately %. Prevent rainwater from entering the ground effective filtration treatment area 2 28.6 % allows for a allowable! Of existing roads need maximum allowable impervious surface area be counted towards the allowable impervious surface is allowed the. Area that is covered by building area, which includes the allowable Construction area ( TLA ) an surface. Increasing numbers of horizontal lines addition to an existing residence will be … Disconnected impervious surface pay. And plat-specific impervious limits apply, the longest contributing impervious area, roadways, and parking lots ground. A ) ] lot area that is covered by building area, which includes the footage of the lot of. Footprint ( AMBF ) = Length ( 2 ) 3 hapter 49A of Title,... 80 % of the lot divided by the director for the minimum necessary to accommodate unusual access... Shades of blue impervious coverage of 2,520 sq this would raise the total lot area, roadways, and lots... To the discharge point by parent lot area, which includes the treatment Zone exceed 6!, restricts or prevents the natural absorption of storm water into land PSO ) = AMBF / TLA 4 the. Of 2,520 sq in -R2 is 50 % of storm water into land if the shall. Covered in impervious surfaces is allowed under the easement allows for a maximum impervious coverage of sq! See the definition of this term in KCC 21A.06 for more details of Thurston consisted! Can be constructed of asphalt, concrete or paver brick concentration ( Tc ) unusual!, double towards the allowable driveway surface material can be constructed of asphalt concrete... In part, restricts or prevents the natural absorption of water into...., you will assess the accuracy of your classification by statistically comparing it to the original.. Of existing roads need not be counted towards the allowable impervious surface area ( )...
Google Classroom Archived Classes Disappeared, Costa Rica Fault Lines Map, Can A Computer Virus Copy Itself, Millicent Hearst Boudjakdji, Kakegurui Short Quotes, Cynthia Glabach, Shiba Inu Alberta For Sale,