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HomeMy WebLinkAboutMINUTES - 07112006 - C.16 TO: BOARD OF SUPERVISORS, AS GOVERNING ��"""sE L''°� Contra BOARD OF THE FLOOD CONTROL& WATER CONSERVATION DISTRICTCosta C / • "� .�,J�mNR� ,� ftp FROM: MAURI:CE M. SHIU, CHIEF ENGINEER ,co' v~�� County - srAuzi't`t DATE: July 11, 2006 SUBJECT: APPROVE and AUTHORIZE the Chief Engineer, Flood Control and Water Conservation District, or designee, to direct payment to California Wildlife Foundation in the amount of $44,489 and the Lindsey Wildlife Museum in the amount of$5,000 for mitigation fees associated with the:implementation of the Lindsey Basin Completion Project and the Relocation and Enhancement of Line Z Project, Antioch area. (Drainage Area 56 Funds) (District V) Project No. 4460-6)(-4451 SPECIFIC REQUEST(S)OR RECOMMENDATION(S)&BACKGROUND AND JUSTIFICATION RECOMMENDED ACTION: APPROVE and AUTHORIZE the Chief Engineer,Flood Control and Water Conservation District, or designee to direct payment of a mitigation purchase in the amount $44,489 to California Wildlife Foundation, a non-profit wildlife protection organization, to manage funds designated to publicly-held wildlife areas and reserves. This money will be used to mitigate for impacts resulting from the implementation of the Lindsey Basin Completion Project and the Relocation and Enhancement of Line Z Project. These funds,minus overhead costs incurred by the California Wildlife Foundation, shall be transferred to the East Contra Costa County Habitat Conservation Plan upon approval of the Plan. APPROVE and AUTHORIZE the Chief Engineer,Flood Control and Water Conservation District, or designee to direct payment of a mitigation purchase in the amount of$5,000 to the Lindsey Wildlife Museum, a non-profit wildlife rescue,rehabilitation,and education organization. This money will be used to mitigate for impacts resulting from the implementation of the Lindsey Basin Completion Project and the Relocation and Enhancement of Line Z Project. Continued on Attachment: ❑ SIGNATURE: 72'!0_, PIRECOMMENDATION OF COUNTY ADMINISTRATOR ❑ RECOMMENDATION OF BOARD COMMITTEE ['APPROVEOTHER SIGNATURE(S)- �� ACTION OF BO ON A/ APPROVED AS COMM DF OTHER ❑ VOT�OF SUPERVISORS I hereby certify that this is a true and correct copy of an action ✓✓ UNANIMOUS(ABSENT taken and entered on the minutes of the Board of Supervisors on AYES: NOES: the date shown. ABSENT: ABSTAIN: CS:sj G:\EngSvc\ENVIRO\BO\2006\(0"?-I1-06)Payment-Lindsey&LineZ.doc ATTESTED: JOHN CULLEN, erk e Board of Supervisors and County Orig.Div:Public Works( Division) Administrator Contact: (Cece Sellgren 3-2296) cc: E.Kuevor,CAO Auditor-Controller Public Works Department: B Deputy Bob Faraone-FC y p ty Cece Sellgren SUBJECT: APPROVE and AUTHORIZE the Chief Engineer, Flood Control and Water Conservation District, or designee, to direct payment to California Wildlife Foundation in the amount of $44,489 and the Lindsey Wildlife Museum in the amount of$5,000 for mitigation fees associated with the implementation of the Lindsey Basin Completion Project and the Relocation and Enhancement of Line Z Project, Antioch area. (Drainage Area 56 Funds) (District V) Project No. 4460-6X-4451 DATE: July 11, 2006 PAGE: 2 of 2 FISCAL IMPACT: There will be no impact to the County General Fund. The total payment of$49,489 will be made from Drainage Area 56 (East Antioch Creek watershed) funds. REASONS FOR RECOMMENDATIONS AND BACKGROUND: The purpose of the overall project is to provide improved flood protection for the communities in southeast Antioch and those downstream in the East Antioch Creek watershed and to implement elements of the East Lone Tree Specific Plan approved by the City of Antioch in 1986. The Lindsey Basin Completion Project will excavate and relocate portions of the detention basin to provide 100-year flood protection to the communities downstream of the detention basin. The Relocation and Enhancement of Line Z will move, increase flood conveyance capacity, and create quality riparian habitat for a 0.8 mile stretch of East Antioch Creek. Asa condition of the regulatory permits and as a result of unexpected wildlife impacts the payments to the wildlife organization are required in order to comply with State law. CONSEQUENCES OF NEGATIVE ACTION: Without approval of payment,the environmental impacts of the projects will not be adequately mitigated as required by the California Department of Fish and Game permit issued for the project. STATE OF CALIFORNIA THE RESOURCES AGENCY ARNOLD SCHWARZENEGGER,GOVERNOR DEPARTMENT OF FISH AND GAME CENTRAL COAST REGION S` Pllid' r (7D7}944-5520 Mailing address: - POST OFFICE BOX 47 pr� YOUNTVILLE CALIFORNIA 94599 APP 18 2006 Street address: 7329 SILVERADO TRAIL CONTRA CG:-TA �cj�r,1TY NAPA CALIFORNIA 94558 PUBLIC WORKS DEPARTMENT April 14, 2006 Notification Number: 1600-2005-0744-3 Mitch Avalon Contra Costa County Flood Control 255 Glacier Drive Martinez, CA 94553 1602 LAKE AND STREAMBED ALTERATION AGREEMENT This agreement is issued by the Department of Fish and Game pursuant to Division 2, Chapter 6 of the California Fish and Game Code: WHEREAS,the applicant Mitch Avalon, Contra Costa County Flood District, hereafter called the Operator,submitted a signed NOTIFICATION proposing to substantially divert or obstruct the natural flow of, or substantially change the bed, channel, or bank of,or use material from the streambed or lake of the following water:Line Z and Lindsey Basin,located in SECTION 34,TOWNSHIP 2N,RANGE 3E,in the County of Contra Costa,State of California;and WHEREAS,the Department has determined that such operations may substantially adversely affect existing fish and wildlife resources including water quality,hydrology,aquatic or terrestrial plant or animal species;and WHEREAS,the project has undergone the appropriate review under the California Environmental Quality Act;and WHEREAS,the Operator shall undertake the project as proposed in the signed PROJECT DESCRIPTION and PROJECT CONDITIONS(attached). If the Operator changes the project from that described in the PROJECT DESCRIPTION and does not include the PROJECT CONDITIONS,this agreement is no longer valid; and WHEREAS,the agreement shall expire on December 31,2007;with the work to occur between April 15 and October 15;and WHEREAS, nothing in this agreement authorizes the Operator to trespass on any land or property,nor does it relieve the Operator of the responsibility for compliance with applicable Federal,State, or local laws or ordinances. Placement,or removal,of any material below the level of ordinary high water may come under the jurisdiction of the U. S.Army Corps of Engineers pursuant to Section 404 of the Clean Water Act; THEREFORE,the Operator may proceed with the project as described in the PROJECT DESCRIPTION and PROJECT CONDITIONS. A copy of this agreement,with attached PROJECT DESCRIPTION and PROJECT CONDITIONS,shall be provided to contractors and subcontractors and shall be in their possession at the work site. Failure to comply with all conditions of this agreement may result in legal action. This agreement is approves!by: . l 1�ltri 61 .C- Robert W. lrke Regional Manager Central Coast Region cc: Janice Gan Lieutenant Christensen Y: . STATE OF CALIFORNIA THE RESOURCES AGENCY ARNOLD SCHWARZENEGGER GOVERNOR DEPARTMENT OF 1=1SH AND GAME CENTRAL COAST REGION i (707)944-5520 Mailing address: POST OFFICE BOX 47 YOUNTVILLE,CALIFORNIA 94599 Sheer address: 7329 SILVERADO TRAIL NAPA, CALIFORNIA 94558 Notification Number: 1600-2005-0744-3 Line Z, Lindsey Basin, East Antioch Creek Contra Costa County Contra Costa County Flood Control 255 Glacier Drive Martinez, CA 94553 Fax 925-313-2333 PROJECT DESCRIPTION and PROJECT CONDITIONS Description . Contra Costa County Flood Control and Water Conservation District (Flood Control District)is proposing_to relocate and enhance an existing ditch-constructed in uplands (Line Z) and complete construction of the Lindsey Detention Basin to manage stormwater flows from existing and proposed urban development and create a riparian corridor in accordance with the City of Antioch's East Lone Tree Specific Plan. The project is located 1/4 mile west ofNeroly Rd and between 3/4 and 1 and 3/4 mile north of Lone Tree Way in southeastern Antioch. The Line Z relocation portion of the proposed project consists of excavating a new channel parallel to the alignment of the State Route 4 Bypass (in construction), transferring flows to the new channel, filling the old channel, and planting riparian species along the toe of slope of the low flow channel to create riparian habitat. The Lindsey Basin portion of the proposed project consists of excavating and filling portions of the upland sections of the detention basin to conform its shape to the new infrastructure under construction (SR4 Bypass and Laurel Rd) or proposed to constructed (Slatten Ranch Rd), removing the existing outlet structure, "daylighting" a portion of Line Z that is currently culverted, installing a new outlet structure, creating a new low flow channel through the expanded detention basin to conform to the new inlet and outlet, planting the new low flow channel with riparian species, and filling the old low flow channel. The proposed project will result in permanent loss of not more than 1.58 acres of annual grassland and a temporal loss of not more than 38.07 acres of annual grassland. There will be a restoration of approximately 1.79 acres of annual grassland as the old channel is filled and an asphalt area reclaimed. Mitigation will be provided for the temporal loss of 38.07 acres consistent with the Draft East Contra Costa HCP/NCCP. The proposed project will result in impacts to approximately 4060 linear feet (0.93 acres) of Page 1 of 7 Operator's initials Date prepared: Notification Number 1600-2005- 44-3 r. waters and 4060 linear feet (0.625 acres) riparian habitat. There will be a approximately 4525 linear feet (0.96 acres) of waters created on site and approximately 0.623 acres of riparian area. There will be a net gain of approximately 465 linear feet (0.03 acres) of waters and 0.437 acres of riparian. The relocated and enhanced Line Z and expanded Lindsey Detention Basin will create quality riparian habitat where none has ever existed before, will create 465 linear feet of additional stream channel (net), and will not add any additional linear feet of hardscape to the completed facilities. The proposed relocation and enhancement of Line Z includes the following elements. 4 Excavating a new Line Z channel in uplands that will have the following dimensions: + 2300 feet in length; 8.48 acres in size + 166 feet wide at top of bank * 10-20 feet wide channel invert * 38 - 64 feet wide low flow channel * 123,000 cubic yards (cy) of excavation * Filling the old Line Z channel (after transferring flows to the new channel) * 3160 feet in length; 3.34 acres + 46 feet wide at top of bank * 10 feet wide at channel invert + 29,000 cy of fill * Removing existing structures from old Line Z channel including: ♦ Three combination culverts/drop structures (creating access to farm fields on both sides of the existing channel). Each structure has the following dimensions: + Culverts are 132" in diameter(Corrugated metal pipes),that are 50 feet long. + 16 foot long drop inlet structure(immediately upstream of the culvert) * 15' linear feet of rock slope protection upstream and downstream of the.entire structure ♦ One existing concrete bridge/11-foot drop inlet structure from the southern (u/s) end of the basin, including concrete rock slope protection downstream of the structure + Constructing two combination culvert/drop structures in new Line Z with approximately 20 linear feet rock slope protection upstream and downstream as needed. * Planting the toe of slope of the new Line Z channel with riparian species (primarily willow and cottonwood cuttings) to create riparian habitat ♦ Additional riparian habitat planting will be installed by adjacent developers as a condition of approval when irrigation services are developed. The completion of the Lindsey Detention Basin includes the following elements: ♦ Relocating the existing detention basin outfall structure 320 feet to the north (downstream) * Removing the existing trash rack and outfall structure + Removing 320 linear feet of concrete primary spillway pipe * Excavating 330 feet of new low flow channel (additional length due to sinuosity) * Constructing a new outfall structure and trash rack and connecting it to the existing Line Z pipe downstream Page 2 of 7 Operator's initials Date prepared.- Notification Number 1600-2005-0 4A-3 ♦ Regrading the detention basin bottom and low flow channel to connect the new basin inlet (d/s end of the new Line Z channel)with the new basin outlet structure. ♦ Existing low flow channel to be filled 900 linear feet. ♦ New low flow channel will be 2225 linear feet ♦ Regrading upland portions of the detention basin to conform to new and planned infrastructure, including: ♦ Excavating 288,000 cubic yards (CY)—mainly in the northern portion of the existing basin. ♦ Placing and compacting 105,000 CY of material into a portion of the basin recently excavated. This area to be filled is generally in the south-east corner of the basin. ♦ Placing and compacting the remaining 262,000 CY of material onto the previously used fill site located north of the proposed Laurel Road (in construction) and South of the Contra Costa Canal. Construction Methodology Excavation of new channel The new line Z channel will be excavated using heavy equipment such as excavators, scrapers, bulldozers, and backhoes as soon as all regulatory permits have been obtained and special status species have been safely removed. The existing Line Z channel will remain operational until dewatering is necessary to prepare the channel to be filled. Flows will be temporarily diverted from the old Line Z channel while dirt from the new Line Z channel is placed in the old Line Z channel. Once the new Line Z is completely excavated, all structures are complete and erosion controlled installed, the flows will be introduced to the new Line Z channel. A berm will be maintained at all', times between the already improved sections of Line Z upstream and the newly constructed sections of Line Z to ensure low flows do not transfer prematurely. Transfer of water between channels The transfer of water generated from the runoff from suburban development will not occur until the new Line Z channel has been completed and erosion control measures have been installed in the channel invert. The construction contractor will develop a plan for Flood Control District approval that will require the maintenance of water quality turbidity standards during the transfer of flows. Fill of old channel While the water flows are transferred to the newly constructed Line Z biological monitors will relocate all native aquatic species to a safe.haven. Upon completion of the water transfer and the relocation of the native wildlife the old Line Z channel will be filled and the old hardscaped features will be. removed. This will be done by typical heavy construction equipment. Planting of new channel The toe of the slope of the low flow channel will be planted with a mix of willow and cottonwood cuttings in the late fall (November—January) after the construction of the new Line Z channel. Although there is sufficient year round run-off from the suburban development upstream to sustain the plantings, these cuttings will not receive supplemental irrigation due to Page 3 of 7 Operator's initials Date prepared: Notification Number 1600-2005-044-3 the complete lack of irrigation facilities within the project area. ]ones and Stokes will develop plans and specifications for a contract to be administered by the Flood Control District. Jones and Stokes will inspect the installation of the cuttings and.conduct compliance monitoring required by the maintenance contract and regulatory permit requirements. The slopes of the low flow channel, benches and upper slopes of the channel will not be planted at this time due to the lack of irrigation infrastructure. The adjacent landowners will complete the planting of the channel facilities as a condition of approval by the City of Antioch once their developments (including irrigation infrastructure) are constructed. Conditions Work within the stream/riparian corridor shall be confined to the period April 15 to October 15. Revegetation work is not confined to this time period but must be completed in the same calendar year. Equipment shall not be operated in wetted areas (including but not limited to ponded, flowing, or wetland areas) or within the stream channel below the level of top-of-bank. Erosion control measures shall be utilized throughout all phases of operation where sediment runoff from exposed slopes threatens to enter waters of the State. At no time shall silt laden runoff be allowed to enter the stream or directed to where it may enter the stream. Only clean rocks and boulders shall be used for the project. To minimize impacts to water resources the Flood Control District will construct the new Line Z channel and install appropriate erosion control in the channel invert prior to introducing any flows. Work must be performed in isolation from the flowing stream. If there is any flow when the work is done, the operator shall construct coffer dams upstream and downstream of the excavation site and divert all flow from upstream of the upstream dam to downstream of the downstream dam. The coffer dams may be constructed with clean river gravel or sand bags, and may be sealed with sheet plastic. Sand bags and any sheet plastic shall be removed from the stream as soon as possible following completion of the applicable phases of the project. Clean river gravel may be left in the stream, but the coffer dams must be breached to return the stream flow to its natural channel. The Operator/Contractor shall check daily for stranded aquatic life as the water level in the dewatering area drops. All reasonable efforts shall be made to capture and move all stranded aquatic life observed in the dewate.red areas. Capture methods may include fish landing nets, dip nets, buckets and by hand. Captured aquatic lifee shall be released immediately in the closest body of water adjacent to the work site. This condition does not allow for the take or disturbance of any state or federally listed species, or state listed species-of special concern. Biological monitors will work in the. old Line Z channel to catch and transfer any native wildlife that is stranded in the old Line Z Channel to the existing section of the improved Line Z channel upstream of the: project area. The proposed project could result in the removal of potential nesting habitat for a variety of Page 4 of 7 Operator's initials Date prepared: Notification Number 1600-2005-0 44-3 passerine species within the upland areas and along Line Z. Upland areas will be disked and all trees and shrubs will be cut prior to the onset of the breeding season (February 1) to prohibit nesting behavior within the project area. The Operator may remove vegetation by hand from March l to August 15 if a qualified biologist conducts a survey for nesting birds within three days prior to the vegetation removal; and ensures no nesting birds shall be impacted by the project. These surveys shall include the areas within 200 feet of the edge of the proposed impact area(s). If active nests are found, a minimum 50-foot (200 feet for raptors) fence barrier shall be erected around the nest site. No habitat removal or any other work shall occur within the fenced nest zone even if the nest continues active beyond August 15, until the young have fledged, are no longer being fed by the parents, have left the nest, and will no longer be impacted by the project. Vegetation clearing MAY occur other than as described above IF Department-approved avoidance measures are in place to ensure no impacis to nesting birds may occur AND the Operator receives confirmation from the Departmenit that the vegetation removal at a specific site is allowed on a specified date. The Operator shall submit the mapped survey results to the Department for review and approval prior to vegetation removal to ensure full avoidance measures are in place. The proposed project could result in the removal of potential nesting habitat and possible direct take of burrowing owls. The Flood Control District will implement a burrowing owl exclusion program prior to the onset of the breeding season (February 1). The Flood Control District has already been in contact with Janice Gan, DFG Wildlife Biologist, to coordinate the implementation of this program. Direct take of burrowing owl or active nests is not authorized. To mitigate the permanent loss of 4060 linear feet (0.93 acres) of waters and 4060 linear feet (0.625 acres) of riparian habitat, the Flood Control District will create 4525 linear feet(0.96 acres) of waters by excavating the new channel and 0.623 acres of riparian area by planting the tow of the slope adjacent to the low flow channel To mitigate for the temporal loss of cattail marsh habitat, the Flood Control District will plant the 4525 linear feet of the toe of the slope of the low flow channel with a mix of willow cuttings to quickly establish 0.62 acres of woody riparian habitat. Runoff from the suburban development will provide ample water to sustain the cuttings planted at the toe of slope. Due to a lack of irrigation infrastructure in the area, the cuttings will not be irrigated. The Flood Control District has hired Jones and Stokes and Associates to develop planting plans, which will be advertised as a separate contract and installed in late fall 2006. The slopes of the channel will be hydroseeded with a mix including native grass and herbaceous species. The proposed project will result in the permanent loss of not more than 1.58 acres of annual grassland and a temporal loss of not more than 38.07 acres of annual grassland. There will be restoration of approximately 1.79 acres of annual grassland as the old channel is filled and an asphalt area reclaimed. Mitigation will be provided for the temporal loss of 38.07 acres consistent with the Draft East Contra Costa HCP/NCCP by providing a payment of$44,489 in the form of a check or cash within 10 day of execution of this agreement. These funds will be held by the California Wildlife Foundation until the East Contra Costa HCP/NCCP is implemented. These funds may be redirected by the Department to an alternate approved Page 5 of 7 operator's initials k;&_ Date prepared.! Notification Number 1600-2005-0 4-3 c conservation effort if the BCP/NCCP is not finalized within 24 months. If any sensitive species are observed in project surveys, the Operator shall submit Natural Diversity Data Base (NDDB) forms to the NDDB for all preconstruction survey data within five working days of the sightings, and provide DFG Region 3 with copies of the NDDB forms and survey maps. To the extent that any provisions of this Agreement provide for activities that require the Operator to traverse another owner's property, such provisions are agreed to with the understanding that the Operator possesses the legal right to so traverse. In the absence of such right, any such provision is void. In the event that the project scope, nature, or environmental impact is altered by the imposition of subsequent pemiit conditions by any local, state or federal regulatory authority, the Operator shall notify the Department of any imposed project modifications that interfere with compliance to Department conditions. If the Operator needs more time to complete the authorized activity, the work period may be extended on a day-to-day basis by Janice Gan, Environmental Scientist at (209) 83506910, or, alternatively,by the Yountville office at (707) 944-5520. A copy of this agreement must be provided to the contractor and all subcontractors who work within the stream zone and must be in their possession at the work site. Building materials and/or construction equipment shall not be stockpiled or stored where they could be washed. into the water or where they will cover aquatic or riparian vegetation. Debris, soil, silt, bark, rubbish, creosote-treated wood, raw cement/concrete or washings thereof, asphalt,paint or other coating material, oil or other petroleum products, or any other substances which could be hazardous to aquatic life, resulting from project related activities, shall be prevented from contaminating the soil and/or entering the waters of the state. Any of these materials, placed within or where they may enter a stream or lake, by Operator or any party working under contract, or with the permission of the Operator, shall be removed immediately. The contractor shall not dump any litter or construction debris within the riparian/stream zone. All such debris and waste shall be picked up daily and properly disposed of at an appropriate site. Department personnel or its agents may inspect the work site at any time. The Operator is liable for compliance with the terms of this Agreement, including violations committed by the contractors and/or subcontractors. The Department reserves the right to suspend construction activity described in this Agreement if the Department determines any of the following has occurred: A). Failure to comply with any of the conditions of this Agreement B). Information provided in support of the Agreement is determined by the Department to Page 6 of 7 Operator's initials Date prepared: Notification Number 1600-2005-07 4-3 be inaccurate. Q. Information becomes available to the Department that was not known when preparing the original conditions of this Agreement (including, but not limited to, the occurrence of State or federally listed species in the area or risk to resources not previously observed) D).The project as described in the Agreement has changed or conditions affecting fish and wildlife resources change. Any violation of the terms of this Agreement may result in the project being stopped, a citation being issued, or charges being filed with the District Attorney. Contractors and subcontractors may also be liable for violating the conditions of this agreement. Amendments and Renewals The Operator shall notify the Department before any modifications are made in the project plans submitted to the Department. Project modifications may require an amendment or a new notification. This Agreement is transferable to subsequent owners of the project property by requesting an amendment. To renew the Agreement beyond the expiration date, a written request for a renewal must be submitted to the,Department (1600 Program, Post Office Box 47, Yountville, California 94599) for consideration at least 30 days before the Agreement expiration date. A renewal requires a fee. The Fee Schedule can be obtained at www.dfe.ca.eov/1600 or by phone at (707) 944-5520. Renewals of the original Agreement are issued at the discretion of the Department. To modify the project, a written request for an amendment must be submitted to the Department (1600 Program, Post Office Box 47, Yountville, California 94599). An amendment requires a fee. The Fee Schedule can be obtained at w-ww.df2.ca.Qov/l 600 or by phone at (707) 944-5520. Amendments to the. original Agreement are issued at the discretion of the Department. Please note that you may not proceed with construction until your proposed project has undergone CEQA review and the Department signs the Agreement. I, the undersigned, state that the above is the final description of the project I am submitting to the Department for CEQA review, leading to an Agreement, and agree to implement the conditions above required by the Department as part of that project. I will not proceed with this project until the Department signs the Agreement. I also understand that the CEQA review may result in the addition of measures to the project to avoid, minimize, or compensate for significant environmental impacts: Operator's name (print): . Operator's signature: Signed the day of / </C,rt/fi _ , 2006 Page 7 of 7 operator's initials Date prepared. Notification Number 1600-2005-'07-44-3 l`) — as`JC'' C^ _ l-or Dcl-:.,j l ase Onh — Notification Number: �� 1t _ %� � Date Received Fee Enclosed? R1'es< ��� 0C ❑?vo Action Taken/Notes STATE OF F - ,f THE RESOUR ES AOGENC) CS' 1" DEPARTMEN'T OF FISH AND GAME L7 NOV 3 0 'iJ05 NOTIFlCA7-]ON OF LAKE OR STREAMBED ALTERATION All fields must be completed unless otherwise indicated. �J 1 ountviHe (See enclosures for instructions.) Notification Type ❑Timber Harvesting Plan(No. ) ❑ Water Application(No. ) ❑Commercial Gravel Extraction(No. ) ® Other Application Information Name Address Telephone/FAX Applicant: Mitch Avalon,Assistant Chief Engineer 255 Glacier Dr. Business: 925-313-2203 Contra Costa County Flood Control and Martinez. CA 94.553 Fax: 925-313-2333 Water Conservation District Operator: Same Same Business: Same Fax: Same Contractor• 2100 Goodvear Road Business: (707)742-b000 De Silva Gates/FCl JV Benicia, CA 94510 Fax: (707)746-0849 (if known) Contact Person: Cece Sellgren, Environmental Planner 255 Glacier Dr. Business: 925-313-2296 Contra Costa County Flood Control (if not applicant) and Martinez. CA 9455, Fax: 925-313-2333 Water Conservation District csell nipw.cccountv.us Property Owner: Contra Costa County Flood Control and Same Business: 925-313-2000 Water Conservation District Fax: 925-313-2333 Project Location Location Description: East Antioch Creek in southeast Antioch,parallel to Segment l of the State Route 4 Bypass— Figures 1-3 County Assessor's Parcel Number �_-ontra Costa County USGS Map Tov nship Range Section Latitude/Longitude 3rentwood 7.5 minute quadrangle 2N 3E 34 N/A Fame of.River,Stream,or Lake: East Antioch Creek Fributary To? San Joaquin River n FG2023 (E1lective.lanuary 12,2004) ?game of Applicant:___ Mitch va Ion. C onna ( osia (rnmty Flood Connol z:nd N iter( onservaIIoil District Project Description Project Relocator; and enhancement of Line Z and completion of the 1 it-dsev Detention Basin No me_� Start Date: 04/15.'.006 Completion 10:1 4.'200r Project �� %I)1111.1100 Number of Stream Dale- Cost: Encroachments:N/A i (Timber Harvesting Plans Only) Describe project below: (Attach separate pages if necessary) Conn-a Costa County Flood Connol and \tl'aier Conservation District (Flood Control District) is proposing to relocate and enhance an existinc ditch constructed in uplands(Line Z)and complete construction of the Lindsey Detention Basin to manage stormwater flows from exisiinc and.propose.d urban development and create a riparian corridor in accordance Nviih the City of Antioch's East Lone Tree Specific Plan (Figures 1-3). The Line Z relocation portion of the proposed project consists of excavating a new channel parallel to the alignment of the State Route 4 BNpass (in construction), nansfenine flows to the nevi channel. filling the old channel, and planting riparian species along the toe of slope of the low flow channel to create riparian habitat. (Figure 4) The Lindsev Basin portion of the proposed project consists of excavating and filling portions of the upland sections of the detention basin to conform its shape to the neve infrastructure under construction (SR4 BNpass and Laurel Rd) or proposed to constructed (Slatten Ranch Rd); removing the existing outlet structure, "daylighung" a portion of Line Z that is curient)v culveried, installing a new outlet structure, creating a new low flow channel through the expanded detention basin to conform to the neva inlet and outlet, planting the new low flow channel -, ith riparian species,and filling the old low flow channel. (Figure 5) The relocated and enhanced Line Z and expanded Lindsey Detention Basin \vill orate quality riparian habitat where none has ever existed before, xvill create 355 linear feet of additional scream channel (net), and will not add any additional linear feet of hardscape to the completed facilities. . ❑ Continued on separate page(s) Attachments/Enclosures Attach or enclose the required documents listed below and check the corresponding boxes. ® Project Description— ® Map shoxa ing project location, including distances and%or ® Construction plans and drawings Attachment#1 directions from nearest city or town—Figures 1-3 pertaining to the project—Figures 4-5 Completed ❑Notice of Exemption ❑Negative Declaration ® Mitigated Negative Declaration CEQA documents: ®Final Environmental Impact Report ®Notice of Determination Copies of applicable ❑ Federal. Request to Corps of Engineers for confirmation of previous determination of lack of federal local. State.or federal jurisdiction under Clean lVater Act(response pending) permits, agreements,or other authorizations: ❑ State. Application for 1A asie Discharge Requirements to Central Valley Regional Water Quality Control Board(in progress) herehN certify that all information contained in this notific-3no.is nue and COMM and that 1 an-. ,uthrn i:ed to Sigri this do(ument. I understand that in the event this information is 'Lind to be untrue or incorrect,I may be subject to civil or criminal prosecution and the Department may consider this notification to be incomplete and/or cancel any Lake or 'reambed Alteration Agreement issued pursuant to this nonfrcation.1 understand that this nntifrcannn is valid only for the project described herein and that)maybe subject to vil or criminal prosecution for undertaking a project that differs from the one described herein,unless i Lzve notified the Department of that project in accordance with Fish and ame Code Section 1602. mderstand that a Department representative may need to inspect the property where the pioect described herein will take place before issuing a Lake or Streambed Alteration erecment pursuant to this notification.in the event the Department determines that a site inspection is necessary,1 hereby authorize the Department to enter the property where e project described herein will take place to inspect the proprm at any reasonable time and certify that 1 on-i authorized to grant the Department permission to access the operty. 1 I request the Department to first contact me at(insert telephone number) to schedule a date and time to enter the property ere the project described herein will tah:e place and understand that this may delay the Department's evaluation of the project described herein. Op for Operator' �ent2tive Date m FG20 3 (Effective January 12,2004) Contra Costa County Flood Control and Water(cmiservation District Relocation and Enhancement of Line 2 and Completion of the Lindsey Detention Bain h6liecl Attachment#1 —Project Description Project Description Contra Costa County Flood Control and '\�7aier Conservation District (Flood Control District) is proposing to relocate and enhance an existing ditch constructed in uplands (Line Z) and complete construction of the, Lindsey Detention Basin to manage sion-nAvater flows from existing and proposed urban development and create a riparian corridor in accordance with the City o,f Antioch's East Lone Tree Specific Plan (Figures 1-3). The Line Z relocation portion of the proposed project consists of excavating a new channel parallel to the alignment of the State Route 4 Bypass (in construction), transferring flows to the new channel, filling the old channel, and planting riparian species along the tae of slope of the low flow channel to create riparian habitat. (Figure-4) The Lindsey Basin portion of The proposed Project consists of excavating and filling portions of the upland sections of the detention basin to conform its shape to The new infrastructure under construction (SR4 Bypass and Laurel Rd) or proposed to constructed (Slatten Ranch Rd), removing the existing outlet structure, "daylighting" a portion of Line Z that is currently culverted, installing a new outlet structure, creating a new low flow channel through the expanded detention basin to conform to the new Inlet and outlet, planting the new low flow channel with riparian species, and filling the old low flow channel. (Figure 5) The relocated and enhanced Line Z and expanded Lindsey Detention Basin will create quality riparian habitat where none has ever existed before, will create 355 linear feet of additional stream channel (net), and will not add any additional linear feet of hardscape to the completed facilities. Purpose & Need In the 1980's the City of Antioch decided to promote the development of suburban housing and businesses to accommodate a regional shortage in housing -",]thin The greater San Francisco Day Area. The Flood Control District reacted to the City of Antioch's plans by developing a watershed-based plan to collect and convey the anticipated increased slormwater. The "Drainage Area 56 Plan" called for The construction of several storm drain lines (some surface based others placed underground) to convey sionn,,vater and the development of a regional detention basins to attenuate up to a 100-year flood flows. This plan was chosen over other options that would have required substantial modifications to existing creeks. In 1989, as the City began to permit the construction of new homes and businesses in the tipper most reaches of the East Antioch Creek watershed, the Flood Control District constructed an interim ditch (Line Z) through upland rangeland and orchards and began the first of many phases of the construction of Lindsey Detention Basin to manage The stormwater from the new development. Neither the Interim ditch nor the initially constructed detention basin were large enough to convey and treat 100-year storm flows from the ultimately built community. In 1996 the City developed The East Lone Tree Specific Plan, which envisioned the transformation of approximately 785 acres of rangeland and orchards into residential, commercial, and office development and the infrastructure to support it within southeastern Page 1 of 6 t onna Costa CnI1MV 1_100d (. 0111101 and\eater C011serNau011 DauIcI Reloc.auon and Ln];ancrn;cnt of 1_ine 2and C ompleuon of ih, l uulse� Delei Basin Project Anachment#1 — Project Description Antioch. An integral part of the Specific Plan called fot rnlar��ini� and relocating at an alignment next to State Route 4 B,,Tass the innenin Line Z channel..cxparnding the Lindsey Detention Basin to accommodate 100 year storm flows, creating) riparian habitat alone the channel, and developing a recreational trail along the channel to Lindsey Basin. As development xvithin southeastern Antioch continues and regional infrastructure like the State Route 4 Bypass is constructed, the Flood Control District needs to complete these regional flood protection facilities to protect these new communities in southeast Antioch, as well as those downstream. All sections upstream of the proposed project have been completed by developers. This is the last stretch of Line Z to be expanded and relocated. Detailed Project Description The proposed relocation and enhancement of Line Z includes the following elements. ♦ Excavating a new Line Z channel in uplands that will have the following dimensions: ♦ 2025 feet in length; 9.73 acres in size ♦ 130 feet wide at top of bank ♦ 10 feet wide channel invert ♦ 38 - 64 feet wide low flow channel ♦ 123,000 cubic yards (cy) of excavation ♦ Filling the old Line Z channel (after transferring flows to the new channel) ♦ 2995 feet in length; 3.44 acres ♦ 46 feet wide at top of bank ♦ 6 feet wide at channel invert ♦ 29,000 cy of fill ♦ Removing existing structures from old Line Z chamnel including: ♦ Three combination culverts/drop structures (creating access to farm fields on both sides of the existing channel). Each structure has the following dimensions: ♦ Culverts are 132" in diameter (Corrigaied metal pipes) that are 50 feet long. ♦ 16 foot long drop inlet structure (immediately upstream of the culvert) ♦ 15' linear feet of rock slope protection upstream and downstream of the entire structure ♦ One existing concrete bridge/l l-foot drop inlet structure from the southern (u/s) end of The basin, including concrete rock slope protection downstream of the structure ♦ Constructing; two combination culvert/drop structures in new Line Z with approximately 20 linear feet rock slope protection upstream and dovmst-eam as needed. ♦ Planting the toe of slope of the new Line Z chatviel with riparian species (primarily willow and cottonwood cuttings) to create riparian habitat ♦ Additional riparian habitat planting will be installed by adjacent developers as a condition of approval when irrigation services are developed. The completion of the Lindsey Detention Basin includes the following elements: ♦ Relocating the existing detention basin outfall structure 320 feet to the north (downstream) ♦ Removing the existing trash rack and outfall structure Page 2 of 6 Contra Costa County Flood Contiol and 1Valff(.011SCTN'allon District Relocation and Enhancement of Line 2 and(,oniplenon of the Lindsey Detention E,:;�in Protea Attachment#1 —Project Description * Removing IIIIA' pipe 1 .2 320 linear feel of concrete primary spillet -aV * Excavating 330 feet of new low flov,, channel (additional length due to Sinuosity) 4 Constructing a new outfall structure and trash rack and corineCI in 2 11 10 the existing Line Z pipe downstream ♦ Regrading the detention basin bottom and low flow channel to connect the new basin inlet (d/s end of the new Line Z channel) with the new basin outlet structure. * Existing low flow channel to be filled 925 linear feet. * New low flow channel will be 2250 linear feet ♦ Regrading upland portions of the detention basin to conform to neNv and planned infrastructure, including: ♦ Excavating 288,000 cubic yards (CY) - mainly in the northern portion of the e--%]!Zlln2 basin. ♦ Placing and compacting 105,000 CY of material into a portion of the basin recently excavated. This area to be filled is generally in the south-east corner of the basin. Placing and compacting the remaining 262,000 CY of material onto The previously used fill site located north of the proposed Laurel Road (in construction) and South of the Contra Costa Canal. Construction Methodology Excavation of new channel The new line Z channel will be excavated using heavy equipment such as excavators, scrapers, bulldozers, and backhoes as soon as all regulatory permits have been obtained and special status species have been safely removed. The existing Line Z channel will remain operational until the replacement Line Z channel has been completed a'nd is ready to accept low flows. A berm will be maintained at all times between The already improved sections of Line Z upstream and the newly constructed sections of Line Z to ensure low flows do not transfer prematurely. Transfer of water between channels The transfer of water generated from the runoff from suburban development will not occur until the new Line Z channel has been completed and erosion control measures have been installed in the channel invert. The construction contractor will develop a plan for Flood Control District approval that will require the maintenance of water quality turbidity standards during the transfer of flows. Fill of old channel While the water flows are transferred to the newly constructed Line Z biological moniiorers will relocate all native aquatic species to a safe haven. Upon completion of the water transfer and the relocation of the native wildlife the old Line Z channel will be filled and the old bardscaped features will be removed. This will be done by typical heavy construction equipment. Page 3 of 6 onn-a r .o5.ta =oumv Flood i onnol and 'Wate.r Consen-anon Disuici Relncauon and L-nhancement of Line L and t:.ompletion of flhc LuAd cy Deiention Bain Project .Anachrnent#I — Project Description Plantin_p of new channel The toe of the slope of the low flow charmel ,vlll be planted Nvith a mix of willow and cottonwood cuttings in the late fall (November— December) after the construction of the new Line Z channel. Although there is sufficient vear round run-off from the suburban development upstream to sustain the plantings, these cuttings will not receive supplemental irrigation due to the complete lack of irrigation facilities within the proje.c.t area. tones and Stokes will develop plans and specifications for a contract to be administered by the Flood Control District. Jones and Stokes Neill inspect the installation of the cuttings and conduct compliance monitoring required by the maintenance contract and regulatory permit requirements. The slopes of the low flow channel, benches and upper slopes of the. channel ,vill not be planted at this time due to the lark of irri`ation infrastructure. The adjacent landowners ,vill complete the planting of the channel facilities as a condition of approval by the City of Antioch once their developments (including irrigation infrastructure) are constructed. Current Conditions Channel Characteristics The interim Line: Z channel is a ditch constructed in uplands designed to convey runoff from suburban development and storm flows from the impervious surfaces associated with development. The interim Line Z channel is 46 feet at top of bank with 2:1 slopes that slough dirt into the channel invert, which is 6 feet across. 11 is important to remember that prior to upstream development there was no stream channel or defined bed and bank in this section of the East Antioch Creek watershed. Pre-development sionn flows infiltrated into the ground and/or sheet flowed across the landscape. Line Z is not a "blue-line" stream and the Army Corps of Engineers has not claimed jurisdiction of it under the Clean Water Act. The channel reach immediately upstream was relocated and enhanced in 2002 by a developer as a condition of approval by the City of Antioch and requirements by the Flood Control District. This reach of Line Z has the same geomorphic characteristics that the proposed project will. It is also fully landscaped, reflecting the ultimate riparian plantings for the channel. Vegetation The Line Z channel invert is covered with cattails, while the slopes support minimal ruderal vegetation (Figures 6-7). Approximately 5 trees grow at top of bank along the 2995 feet of channel length. No special status species are believed to.occur. Adjacent upland areas consist mostly of abandoned orchards, fields, and grazing lands. Many areas are disked. Vegetation is dominated by grasses and "weedy" herbaceous plants. Wildlife Habitat There are two distinct wildlife habitats associated with the proposed project areas (both the channel and the detention basin): The upland non-native grasslands and the aquatic habitat associated with the channel itself. The upland habitat supports a number.of common insect, Page 4 of 6 Contra Costa County Flood Connol and \eater C.on�ervauon District Relocation and Enhancement of Line . and C otnplcuon of the Lindsey Detention l .: m Pnoiecl Attachment#1 —Project Description reptile,bird, and mammal species. On a re.c.ent site visit wesiern fence Ii-ard, pheasant. red tail hawk, turkey vulture, rabbit, squin-el. and coyote were either directly nhserved or suns observed. Please see Attachment #2: Habitat Assessment for Lindsey Basin and hast Antioch Creek Flood Control Channel by Wildlife Research Associates for a full discussion. Listed Species There are five special status species with the some potential to occur at the project site. ♦ California tiger salamander— The project area is outside of the range for this listed species. Therefore no impacts will occur to this species. ♦ California red-legged frog—Bases upon previous focused protocol-level surveys conducted in 2001 by Sycamore. and Associates: this species does not occur within Line Z. ♦ Northwestern pond turtle — There is no potential habitat within Lindsey Basin or Line Z and no known sitings within five miles. Therefore no impacts will occur to this species. ♦ Nesting passerines— There is a high potential for passerines to nest in the project area and associated habitats. Mitigation measures are outlined below. ♦ Western burrowing owl — This species is known to occur within the project site. Mitigation measures are outlined below. Please see Attachment #2: Habitat Assessment for Lindsey Basin and East Antioch Creek Flood Control Channell by Wildlife Research Associates for a full discussion. Mitigati®n Measures A number of mitigation measures will be employed to ensure impacts to sensitive habitats and species are avoided and minimized where feasible. These measures include: Passerine Nesting Habitat The proposed project could result in the removal of potential nesting habitat for a variety of passerine species within the upland areas and along Line Z. Upland areas will be disked and all trees and shrubs will be cut prior to the onset of the breeding season (February 1) to prohibit nesting behavior within the project area. Please see Attachment 42: Habitat Assessment for Lindsey Basin and East Antioch Creek Flood Control Channel by Wildlife Research Associates for full discussion. Burrowing owl exclusion The proposed project could result in the removal of potential nesting habitat and possible direct take of burrowing owls. The Flood Control District will implement a burrowing owl exclusion program prior to the onset of the breeding season (February 1). The Flood Control District has already been in contact with Janice Gan, DFG Wildlife Biologist, to coordinate the implementation of this program. Please see Attachment #2: Habitat Assessment for Lindsey Basin and East Antioch Creek Flood Control Channel by Wildlife Research Associates for full discussion. Page 5 of 6 Comra Gnsta (..ounty F1 nod CGino] and \A aiei Conser%auon Distnc: Relocation and Enhancemcni of l_nx 2 and (I ompletion of flee l.mdsev Deiemion Basin Project Attachment #t —Project Description 7tansfet of water flow from old channel to new channel 7o minimize irnpac.Is to Nater resources the Flood Control District N ilIcon struct the new Line Z channel. install appropriate erosion control in the channel invert prior to introducing any flows. Biological monitors will work in the old Line Z channel to catch and transfer any native wildlife that is stranded in the old Line Z Channel to the existing section of the improved Line Z channel upstream of the project area. Plantin_q plan To mitigate for the temporal loss of cattail marsh habitat, the Flood Control District will plant the toe of the slope of the low flow channel with a mix of N illow and cottonwood cuttings to quickly establish woody riparian habitat. Runoff from the sul-)m-han development Neill provide ample eater to sustain the cuttings planted at the toe of slope. Due to a lack of irrigation infrastructure in the area, the cuttings will not be irrigated. The Flood Control District has hired Jones and Stokes and Associates to develop planting plans, which -xvill be advertised as a separate contract and installed in late fall 2006. The slopes of the channel will be hydroseeded with a mix including native grass and herbaceous species. Page 6 of 6