Loading...
HomeMy WebLinkAboutBLD2021-00078-05- STORMWATERstormwater calc worksheet QR code – REV. 5/31/2019 page 1 of 2 DEPARTMENT OF COMMUNITY DEVELOPMENT 621 Sheridan Street, Port Townsend, WA 98368 Tel: 360.379.4450 | Fax: 360.379.4451 Web: www.co.jefferson.wa.us/communitydevelopment E-mail: dcd@co.jefferson.wa.us STORMWATER CALCULATION WORKSHEET PARCEL # PROJECT/APPLICANT NAME: DETERMINING STORMWATER MANAGEMENT REQUIREMENTS: This stormwater calculation worksheet should be completed first to classify the proposal as “small,” “medium,” or “large.” The size determines whether a Stormwater Site Plan is re quired in conjunction with a stand-alone stormwater management permit application, building permit application, or other land use approval application that involves stormwater review. The basic information will also be helpful for completing a Stormwater Site Plan, if required. Land-disturbing activity is any activity that results in movement of earth, or a change in the existing soil cover (both vegetative and non-vegetative) and/or the existing soil topography. Land disturbing activities include, but are not limited to clearing, grading, filling, excavation, and compaction associated with stabilization of structures and road construction. Native vegetation is vegetation comprised of plant species, other than noxious weeds, which reasonably could have been expected to naturally occur on the site. Examples include species such as Douglas fir, western hemlock, western red cedar, alder, big -leaf maple, and vine maple; shrubs such as willow, elderberry, salmonberry, and salal; herbaceous plants such as sword fern, foam flower, and fireweed. LAND DISTURBING ACTIVITY, CONVERSION OF NATIVE VEGETATION, AND VOLUME OF CUT/FILL Calculate the total area to be cleared, graded, filled, Answer the following two questions related to excavated, and/or compacted for proposed development conversion of native vegetation: project. Include in this calculation the area to be cleared for: Does the project convert ¾ acres or more of native vegetation to lawn or landscaped areas? Circle: Yes No Does the project convert 2 ½ acres or more of native vegetation to pasture? Circle: Yes No Indicate Total Volumes of Proposed: (Includes BMP T5.13 Fill Volume) Construction site for structures _________________ sq/ft Drainfield, septic tank, etc. ________ 5042________ sq/ft Well, utilities, etc. ___________________________ sq/ft Driveway, parking, roads, etc. ___________________sq/ft Lawn, landscaping, etc. ______________________ sq/ft Other compacted surface, etc. _________________ sq/ft Temporary construction area ______________ sq/ft Total Land Disturbance __________6922___ sq/ft Cut __________ Fill __________ (cu/yd) PARCEL SIZE (I.E., SITE) Size of parcel _________ acres An acre contains 43,560 square feet. Multiply the acreage by this figure. Size of parcel in square feet _________________ sq/ft Scan the QR code to access the digital form 002283013 Herbert C. McClure, Jr. 1.59 94 69,261 1880 stormwater calc worksheet QR code – REV. 5/31/2019 page 2 of 2 ~ Applicants for “small” projects must comply only with Minimum Requirement #2—Construction Stormwater Pollution Prevention. Please submit the Small Project Certification (Worksheet “s). The proponent is responsible for employing the 12 Elements to control erosion and prevent sediment and other pollutants from leaving the site during the construction phase of the project. Pick u p the Construction Stormwater Pollution Prevention (SWPPP) Best Management Practices (BMPs) Fact Sheet. ~ Applicants for “medium” projects—those that must meet only Minimum Requirements #1 through #5 must submit Worksheet A1 and B1, a stormwater site plan and a construction stormwater pollution prevention site plan (See Reference A1A and B1A for guidance).). ~ “Large” projects—those that must meet all 9 Minimum Requirements— must submit Worksheet A1 and B1, a stormwater site plan and a construction stormwater pollution prevention site plan (See Reference A1A and B1A for guidance). Large projects also may require engineering. See Worksheet L to determine additional large project requirements. APPLICANT SIGNATURE By signing the Stormwater Calculation Worksheet, I as the applicant/owner attest that the information provided herein is true and correct to the best of my knowledge. I also certify that this application is being made with the full knowledge and consent of all owners of the affected property. ________________________________________ (LANDOWNER OR AUTHORIZED REPRESENTATIVE SIGNATURE) (DATE) STORMWATER CALCULATIONS – IMPERVIOUS SURFACE Impervious surface is a hard surface that either prevents or slows the entry of water into the soil as under natural conditions prior to development. A hard surface area which causes water to run off the surface in greater quantities or at an increased rate of flow from the flow present under natural conditions prior to development. Common impervious surfaces include, but are not limited to roof tops, walkways, patios, driveways, parking lots or storage areas, concrete or asphalt paving, gravel roads, packed earthen materials, and oiled, macadam or other surfaces which similarly impede the natural infiltration of stormwater. NEW EXISTING Structures (all roof area) _________________sq/ft Structures (all roof area) _________________sq/ft Sidewalks Sidewalks _________________sq/ft Patios Patios _________________sq/ft Solid Decks ______ 81________sq/ft _________________sq/ft _________________sq/ft Solid Decks _________________sq/ft (without infiltration below) (without infiltration below) Driveway, parking, roads, etc _______________sq/ft Driveway, parking, roads, etc _______________sq/ft Other _________________sq/ft Other _________________sq/ft Total New _________________sq/ft Total Existing _________________sq/ft TOTAL NEW + TOTAL EXISTING* _________________sq/ft *This amount will be used to check total lot coverage. DEVELOPMENT v. REDEVELOPMENT Does the site have > 35% or more existing impervious surface? The proposal is considered new development. Answer questions in Figure 2.4.1 Flow Chart for New Development to determine project size (next page). The proposal is considered redevelopment Answer questions in Figure 2.4.2. Flow Chart for Redevelopment to determine project size (next page). yes no 1264 1345 1834 747 2581 3926 1/26/2021 Divide the total existing impervious surface above by the size of the parcel and convert to a percentage. 3.73% Worksheet S Small Project Certification Permanent and temporary drainage on site is designed to divert Stormwater away from my onsite septic system or any neighboring onsite septic system. Yes no Yes no Yes no I understand that my project must comply with Minimum Requirement #2 in the Department of Ecology Stormwater Management Manual as amended. I have read the Construction Stormwater Pollution Prevention Fact Sheet and will implement Best Manage- ment Practices (BMP’s) as applicable to my project. This certification may only be used if you answer yes to all of the questions below (circle yes or no) . Otherwise, a submitt al prepared by a licensed engineer may be required. If located in a Seawater Intrusion Protection Zone (SIPZ), I am able to infiltrate stormwater onsite using a dry- well or other method (full dispersion, downspout dispersion). My project will not discharge stormwater runoff into a critical area (including but not limited to: geohazard area or its 30-foot buffer, wetland or Fish and Wildlife Habitat Conservation Area) Applicant Signature By signing the small project certification, I as the applicant/owner attest that the information provided herein is true and correct to the best of my knowledge. ________________________ (landowner or authorized representative signature) (date) My proposal is a small project, which means it will create less than 2,000 square feet of new, replaced, or new plus replaced impervious surface area, and has less than 7,000 square feet of land disturbing activities as defined on the Stormwater Calculation Worksheet. Yes no 1-26-2021 X X X X X X X XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX X X X X X X E E W W E E E E W W W W (E ) S W (E ) S W (E ) S W (E ) S W (E ) W (E ) W (E ) E (E ) E X X (E ) S W (E ) S W FA R N S W O R T H P L . 8 9 ° 0 5 ' 3 2 " 1 5 0 .0 0 ' S E 1 ° 0 7 ' 4 5 " 4 5 2 . 8 5 ' N E 1 ° 0 7 ' 4 5 " 4 5 2 . 8 5 ' S W 8 9 ° 0 5 ' 3 2 " 1 5 0 .0 0 ' N W (E ) D R I V E W A Y 1 0 6 ' L . A P P R O X 1 % SL O P E D O W N T O S T R E E T ( 7 4 7 S F ) (E ) F EN C E & G A T E (E ) W AT E R M E T E R CO N N E C T ( E ) U N D E R G R O U N D P O W E R L I N E S CO N N E C T T O ( E ) U N D E R G R O U N D W A T E R S E R V I C E L I N E 2 0 ' - 0 " RE A R S E T B A C K S I D E S E T B A C K FR O N T S E T B A C K S I D E S E T B A C K (E ) F EN C E S N DE M O L I S H 1 1 9 2 S F W O O D - F R A M E D SI N G L E F A M I L Y R E S I D E N C E A N D P I E R BL O C K S S U P P O R T I N G F L O O R F R A M I N G (E ) C U L V E R T & S T O R M W A T E R DR A I N A G E R O U T E (E ) E DG E O F P A V I N G PR O P E R T Y L I N E PR O P E R T Y L I N E IN I T I A L A N D R E S E R V E DR A I N F I E L D A R E A (E ) G A R A G E / S H O P / S T O R A GE T O R E M A I N ( 7 7 0 S F ) (E ) U N P L U M B E D S H E D # 1 TO R E M A I N ( 4 2 S F ) (E ) UN P L UM B E D S H E D # 2 T O R E M A I N ( 3 6 0 S F ) CE N T E R L I N E O F R O A D 5 ' - 0 " 5 ' - 0 " 5 ' - 0 " 3 0 ' - 0 " E A S E M E N T 6 0 ' - 0 " A C C E S S 0' 20 ' D P A 3 0 ' - 0 " DOWNSLOPE PROTECTIVE AREA. NO EQUIPMENT, STOCKPILING OF MATERIALS, OR ANY CONSTRUCTIONACTIVITIES (EXCEPT THOSE ACTIVITIES NECESSARYFOR THE CONSTRUCTION OF THE GLENDON SYSTEM AS OUTLINED AND AUTHORIZED BY STATE AND GLENDON BIOFILTER GUIDELINES AND CONSTRUCTION POLICIES) ARE ALLOWED WITHIN THE DPA BOTH BEFORE AND DURING INSTALLATION OF THE SYSTEM AND FOR THE LIFE OF THE SYSTEM. SI T E P L A N LE G E N D & A B B R E V I A T I O N S R 5 0 ' - 0 " R 1 0 0 ' - 0 " EXISTING STORMWATER DRAINAGE ROUTE DP A EXISTING DOMESTIC WATER LINE (UNDERGROUND)EXISTING POWER LINE (UNDERGROUND)SETBACK LINEPROPERTY LINE EXISTING FENCE (E ) UN P L UM B E D S H E D # 3 T O R E M A I N ( 1 0 0 S F ) (E ) U N P L U M B E D S H E D # 4 TO R E M A I N ( 2 7 6 S F ) 4 6 ' - 6 " 10 8 ' - 6 " (E ) W E L L (E ) W E L L H O U S E AB A N D O N & F I L L ( E ) S E P T I C T A N K AP P R O X . L O C A T I O N O F ( E ) L A T E R A L S (T O B E A B A N D O N E D ) 10 0 0 G A L S E P T I C T A N K 10 0 0 G A L P U M P C H A M B E R IN I T I A L G L E N D O N B I O F I L T E R M 3 1 U N I T S SE P T I C S Y S T E M P E R M I T # S E P 1 9 - 0 0 1 3 8 : 4" G R A V I T Y S E W E R T R A N S P O R T P I P E (3 ) ( E) F R U I T T R E E S 6 " , 8 " A N D 1 2 " ⌀ 1 0 ' - 0 " NE W S I N G L E F A M I L Y R E S I D E N C E : IN C L U D I N G R O O F O V E R H A N G , C O V E R E D DE C K S A N D P O R C H E S : ( 1 2 6 4 S F ) IM P E R V I O U S A R E A C A L C U L A T I O N S EX I S T I N G I M P E R V I O U S A R E A : EX I S T I N G D R I V E W A Y 747 SF EX I S T I N G G A R A G E / S H O P / S T O R A G E 770 SF EX I S T I N G S H E D # 1 42 SF EX I S T I N G S H E D # 2 360 SF EX I S T I N G S H E D # 3 100 SF EX I S T I N G S H E D # 4 276 SF 2581 SF TOTAL NE W I M P E R V I O U S A R E A : NE W S I N G L E - F A M I L Y R E S I D E N C E I N C L U D I N G R O O F O V E R H A N G , C O V E R E D D E C K , & C O V E R E D P O R C H E S 1 2 6 4 S F NE W E X T E R I O R C O N C . S T E P S , L A N D I N G S A N D W A L K W A Y S 81 SF 1345 SF TOTAL NE W U N C O V E R E D C O N C . L A N D I N G S (3 6 S F T O T A L ) NE W W A L K W A Y ( 4 5 S F ) 60 ' 40 ' EXISTING IMPERVIOUS AREA 6 3 ' - 0 " 2 0 ' - 0 " 36 ' - 0 " 6 ' - 0 " 5' - 4 1 / 2 " 3 0 ' - 10 " 14 ' - 1 0 1 / 2 " 12 ' - 0 " PR O P O S E D HO U S E SE P T I C P E R M I T # : SEP 19-00138 NEW IMPERVIOUS AREA A P P R O X . 3 ' - 9 " 1 1 6 ' 1 1 5 ' 1 1 4 ' 1 1 3 ' TOPOGRAPHIC LINE - A P P R O X . E X I S T I N G E L E V A T I O N ST O R M W A T E R O P T I O N # 2 : DO W N S P O U T S T O D R Y W E L L 30 ' - 0 " PR O P O S E D B U I L D I N G : HOUSE: 7 2 0 S F COVERED PORCHES & DECKS: 288 SF DATE:DUNGENESS DESIGN KARLA FORSBECK, WA ARCHITECT #6001 520 N. SEQUIM AVE. SEQUIM WA 98382 360-477-5473 karla@dungenessdesign.com PARCEL NUMBER # 002283013 ADS11/26/2021HERBERT C. McCLURE, Jr.McCLURE RESIDENCE 460 FARNSWORTH PLACE, SEQUIM, WA 98382 1" = 6 0 ' - 0 " 1 SI T E P L A N . DEMOLITION &STORMWATER SITE PLAN